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COMPUTERS Troubleshooting Your PC; Pt.1 A PC can be a frustrating beast when things go wrong. Here’s some good advice on problem solving & staying out of trouble in the first place. By BOB DYBALL Most people will, at some time or another, have problems with their PC. Unfortunately, when it comes to fixing those prob­lems, they often make things a lot worse before a “doctor” is finally called in. And that’s where the expense starts – computer technicians cost time and money. It doesn’t have to be like that, though. A little careful diagnosis will usually eliminate the need for a service call and save your valuable time, data and money. Provided you adopt a logical approach to troubleshooting, 12  Silicon Chip you can easily prevent minor prob­lems from becoming major headaches. In this first article on computer troubleshooting, we’ll take a look at common software and hardware problems. We’ll also tell you how to fix them and give some tips to prevent them from happening in the first place. Don’t panic Remember Corporal Jones from Dad’s Army? His reaction to a crisis was to always shout “don’t panic, don’t panic”; this while he flapped about in absolute panic. It’s good advice when it comes to PC problems as well but unlike Corporal Jones, you should remain calm when things go wrong. If your PC suddenly stops responding, for example, don’t immediately switch it off or press the reset button on impulse. The problem is unlikely to get any worse if you leave the comput­er on and you might even be able to recover some data that would otherwise be lost. Of course, if you smell something “cooking” inside the PC or if you see smoke erupting from under the bonnet, then switch off immediately. Most chips don’t work too well after their magic smoke escapes! Software problems Sometimes there can be an inordinately long delay before Windows responds. When it finally does, you Fig.1 (above): you can usually shut down a program that’s not responding in Windows 95 by pressing Ctrl-AltDel. This is far better than just pressing the Reset button on the PC. Fig.2 (right) shows the options you should choose to format a floppy disc for virus checking on another PC. may find that a “blue screen” error message appears. If this happens, just follow the on-screen prompts to shut down the offending program. If the screen goes black or the system has been very slow for some time, check to see if the hard disc light is still flashing. If it is, try waiting it out. Even with a truckload of RAM, occasional long delays can occur while your programs argue about whose turn it is to write data to the hard disc drive. In short, be patient and give the machine sufficient time to complete its tasks. Exporting large files from several popular drawing packages can take quite some time, for example, with lengthy periods of apparent inactivity. If, after a lengthy wait, you are satisfied that the ma­chine has “hung”, hold down the “Ctrl” and “Alt” keys and then press the Delete (Del) key (ie, press Ctrl-Alt-Del). If you are running Windows 95, this will bring up the “Close Program” window – see Fig.1. As shown in Fig.1, this dialog box lists the programs that are open. It even shows “Systray” which is the System Tray at the far right of the taskbar. Look through this list for anything with [Not Responding] after the program name. You can then close down any program that is not responding by clicking on it (to highlight the entry) and then clicking the “End Task” button. This will close down the offending program, after which you should be able to return to the operating system. Although data may be lost when you close a program in this way, it is usually only back to where you last saved your work. At the same time, there is usually no affect on other programs that may be open or on the operating system itself. Any other files that may be open in other programs can now be saved and the system shut down and re-booted in an orderly fashion. This is certainly much better than hitting reset if the system has gone on strike. Pressing reset or turning off a PC without properly shutting down Windows can result in directory problems, lost clusters and cross-linked files. And these prob­lems, in turn, result in lost data. Occasionally, even when a program is no longer responding, you might find that some of your most recent work is still vis­ible on the screen. In this case, you could try hitting the Print Scrn key and pasting the resulting screen capture into the Paint program. This can then be printed out and used as a guide when you later re-enter the information. Alternatively, you can use something as crude as a pencil to jot down vital details. For example, if your browser crashes after you’ve spent ages searching for a vital web site, jotting down the URL (ie, the website address) before closing the program down can save you a lot of searching later on. Intermittent problems Software problems that occur intermittently can easily be confused with hardware problems. If you find that a particular problem occurs in just one program or in one part of DOS or Windows, try running ScanDisk to see if there are any directory or file errors on the hard disc. Sometimes, you will find that a file has been damaged, or even the swap­file used by Windows may be corrupted. Running ScanDisk will usually fix such problems but note that there are a couple of precautions to take when running ScanDisk (see “Setting ScanDisk To Run Automatically”). In some cases, a file may be damaged in a program you are using or in some other part of the system. This can give rise to ob­scure errors such as illegal OPCodes or General Protection Faults (GPFs). Tracking down the offending program is not always easy. That’s because the program that’s affected by the problem is not always the cause of the problem itself. In this sort of case, it’s generally best to follow the procedure listed below: May 1998  13 COMPUTERS: Troubleshooting Your PC (1). Run ScanDisk (or Chkdsk on older computers). (2). Uninstall and then reinstall the offending program. (3). Double check that you are running the latest video drivers, mouse drivers (if you have a non-standard mouse), sound drivers, network card drivers and so on. Up-to-date drivers can usually be downloaded from the manufacturer’s web site. (4). Install any service packs, patches or updates that might be available for your software (again, check the web sites for these). There are service packs for Windows 95 (OSR1), Windows NT, Microsoft Office 97 and Visual Studio, for example. (5). If you are having trouble with a game, check to see if you have the latest Direct X drivers installed and that there are no updates to the game itself. (6). If problems still exist, reinstall Windows. Although reinstalling Windows and Windows applications can be time consuming, it is usually quite a safe procedure. However, some applications can reset things like templates and macros, so try to make backups of these just in case (back up your data files as well). A potential problem here is that some install programs will not over­ write existing files that have the same name. This means that if a file has become corrupted, reinstalling the software will not fix the problem. The answer here, of course, is to remove the offending pro­ gram by uninstalling it. Any remnants of the program that have been left behind after the uninstall procedure should be manually deleted. For this reason, it always pays to check on the program location before uninstalling it, so that you will know where to look for anything that’s been left behind. Only rarely should you have to reformat the lot and start again. This rather drastic procedure usually means a lot more work but sometimes there’s just no other choice, particularly if you suspect that the hard drive has a defect. Reformatting the lot When ever I hear of someone doing this to a Windows 95 installation, I always try to discover their reasons. And in most cases, I’ve found that reformatting the drive wasn’t really necessary or only became necessary because the user didn’t know what he or she was doing. If you don’t have an up-to-date virus checker, then get one – now! If you do have a virus checker, be sure to use it regularly. 14  Silicon Chip Consider, for example, one of my friends who owns an old 486DX4/100. He was playing around in the CMOS one day, when he came across the >504Mb setting. Thinking that this looked like a good thing because he had a 1GB drive, he turned it on only to find that his computer would no longer boot up. Unfortunately, he didn’t put two and two together at the time. Thinking that the problem was due to a virus, he decided to use FDISK /mbr (to rewrite the master boot record) which only made things worse. His problems only ended a few days later after he asked me what the >504Mb setting really meant. By then, of course, it was too late, as he’d completely upset his system – so much so that it was now necessary to reformat the drive and reinstall all his software. Basically, there are two places to be very careful of when exploring your system: (1) the partition table, which is usually accessed through the FDISK.EXE program; and (2) the CMOS set­tings, usually accessed by pressing Del or Ctrl-Alt-Esc during initial boot up. I think I have a virus! If you think you might have a virus, again don’t panic. Most viruses will simply make your system crash more often but some can corrupt or even delete files on your hard disc drive. Apart from a few rather nasty viruses, most do not normally format your hard disk drive – well not immediately! A virus would not spread very far if it was made too obvious. There is also no way that a virus can cause hardware damage – at least, not that I know of. Having said that, most older viruses tend to be quite obvi­ous under Windows 95 because they make it unstable. And quite often, they only allow an infected machine to be booted into safe mode with some obscure error or another. However, a virus is not the only reason why a machine will only boot into safe mode. If you have installed old CD-ROM drivers, for example, then don’t be surprised if you are stuck in safe mode until you remove them and go back to 32-bit Windows 95 drivers. Of course, the way to prevent viruses is to install an up-to-date virus scanner on your computer and use it If a scanner or some other piece of hardware is not responding properly, check that its interface card is properly seated in its slot on the motherboard and that all the cables to it are correctly plugged in. Check also for IRQ conflicts. regularly. If you don’t have a virus checker and you suspect a virus, you can diagnose the problem by formatting a blank floppy disc and plac­ing the system files on it. To do this, insert a floppy disc into the drive, go to the DOS prompt and type format a:/s/u (assuming that the disc is in the A: drive). Alternatively, if you are using Windows 95, you can right click the A: drive in My Computer (or Windows Explorer), click the Format option, and then click the buttons as shown in Fig.2. This will create a bootable floppy disc. Now copy over a couple of .EXE files, a couple of .COM files and, if you think you have a “Macro Virus”, a couple of .DOC files – try to select files that you think may be infected or have been used recently. If you have a virus, then this disk should be well and truly infected. Now ask someone with an up-to-date virus checker on another (uninfected) PC to check this diskette for you. This should give you a reliable idea of what is there. If you are going to check your own system out, make sure you do so with the latest version of a good virus checker. A check each time the system boots up is a good idea in many cases, particularly if you download a lot of material off the net or regularly receive files from other sources. CMOS setup Most problems here usually fall into one of two catego­ries: (1) either someone has fiddled with the CMOS settings; or (2) the backup battery has gone flat and the settings have been lost. Only rarely do CMOS settings become scrambled of their own accord. If you want to try different CMOS settings, be sure you try only one thing at a time. That way, you can easily restore the setup if the machine no longer functions correctly. There are excellent guides on the internet for both AMI BIOS (www.ami.com) and Award BIOS (www.award.com), with both giving detailed expla­nations of each function in the CMOS setup. If you wish to reinstall a hard disk drive, make sure you note the original settings as it might not be using the default mode listed under auto-detect. Sometimes, the bus speed setting can be quite critical, particularly in older ISA bus computers. I remember coming across more than one computer where 7.15MHz worked but 6MHz or 8MHz did not. Apart from rare quirks due to different I/O cards, mother­boards and VGA cards not working together, most older 16bit ISA cards don’t like going above 8MHz, while older 8-bit ISA cards should be run at 4.77MHz If the backup battery is on the way out, you’ll usually find that the PC’s clock no longer keeps good time. This fact can be used as a warning that the battery is about to fail and that now might be a good time to check the CMOS settings and jot them down on a piece of paper. In particular, you should note the settings for the hard disc drive. In fact, it’s always a good idea to record the CMOS set­tings on paper when you first get your computer. This piece of paper should then be kept in a safe place, so that it can be easily found when required. A good trick is to tape it to the bottom of the case. Replacing the backup battery is usually a straightforward exercise. If the battery is soldered in, check (in your mother­board manual) to see if you can run an external battery and if so, what voltage is needed. Three or four AA alkaline batteries in a holder are often all you need to get going again. Note that there is often a jumper on the motherboard to disable the on­board battery and enable the external battery, so check the manual carefully. Also, be sure to remove the May 1998  15 COMPUTERS: Troubleshooting Your PC old bat­tery from the motherboard. If it’s left there, it will eventually leak and cause damage. You don’t have to de-solder the battery; just use a pair of sidecutters to cut the leads. CMOS setup & the hard disc The first thing to realise here is that an IDE hard disc drive might not always be set up according to the par­ ameters on its sticker. For example, a drive with 2000 cylinders, 4 heads and 32 sectors per track might have been “mapped” to 1000 cylin­ders, 8 heads and 32 sectors per track to allow it to work with DOS which can only handle a maximum of 1024 cylinders, 16 heads and 64 sectors. Although drive manager software can extend DOS to provide access for larger hard disc drives, these factors mean that auto-detecting the hard disc in CMOS at some later stage can cause problems. Often, the machine won’t even boot or, if it does, data may be missing or corrupted. Typically, this might happen in a system if you had been running DOS and Windows 3.1x and then later upgraded to Windows 95. If you have lost your CMOS setup and don’t know the head, cylinder and sector settings for your hard disc drive, try auto-detecting it first. Often you will get two or three options for the mode setting. For larger hard disc drives, try picking the one labelled LBA mode, then reboot and rather than go into Wind­ows, press shift-F5 to drop to the DOS prompt. Now try running ScanDisk to see if there are directory structure problems. If you get lots of directory errors, then DO NOT use ScanDisk to fix the problems. Instead, go back into the CMOS setup and try one of the alternative mode selections. (Important: do not write to the hard disk during Fdisk, The Partition Table & Virus Basics The partition table is stored on the very first sector of the hard disc. It consists of the table itself (which is really just a few bytes) plus the partition loader. Because the system loads the partition loader from the first sector of the hard disc, you can boot different operating systems (eg, you can have a dual-boot Windows NT/Windows 95 system). This same feature also allows patches to the operating system to be loaded. A typical example here is a device driver to allow the operating system to handle a hard disc drive that’s larger than it was originally designed to handle. The downside of this is that the same tricks are used by some virus writers to get a virus running before your anti-virus software gets started. Some viruses are even smart enough to piggy-back onto some anti-virus programs and infect everything in sight while a virus scan is actually under way. If you use a disc manager of some sort, use a utility such as Norton Utilities Disk Edit to make a backup copy of the parti­tion loader and partition table in case of problems. If you don’t have a disc manager program running and you suspect a boot sector virus, it’s quite easy to restore the master boot record. Simply boot from a clean floppy disc that also contains the Fdisk.exe utility and, at the DOS A: prompt, type: Fdisk /MBR This undocumented command writes a fresh copy of the parti­tion loader program to your hard drive but leaves the data table as it was. It effectively removes simple partition infectors such as the Stoned and Michelangelo viruses. Note that this procedure will not work on systems with special partition loaders. In particular, do not use it if your system uses a disc manager to provide large hard disc access or if you use an encryption or security program. Some anti-virus programs might also get upset when you first reboot but this is not usually a problem. 16  Silicon Chip this procedure. If ScanDisk were to write back to the hard disc, chances are you could lose data when it started correcting things like the FAT table). Another way of checking that you have the correct settings is to run FDISK at the DOS prompt (boot from a floppy), then pick 4 to display the partition and look for it using 100% of the drive. Preventing software problems Some of the following tips might seem obvious after you’ve “broken” things a few times. However, by taking a few simple precautions, you will minimise down-time and often eliminate crashes altogether. (1). Don’t run too many programs at once without either adding extra RAM or waiting for things to happen. It is quite possible to run a good number of large programs at the same time under Windows 95 but you must be patient. So how much is too much to expect from your PC? Well, until fairly recently, I ran an old 486 DX2-66 machine at home with just 8Mb of RAM. It wasn’t all that quick running Windows 95 but I was still able to cook up some huge spreadsheets and do some pretty nifty programming. If you are short on RAM or have a slow PC, then wait it out – watch the hard disc light and don’t get too impatient if noth­ i ng happens for some time. All those open programs and data files have to fit somewhere and that somewhere if you don’t have enough real RAM is the “swapfile” on the hard disc. And writing to the hard disc is much, much slower than writing to RAM. (2). Systray “widgets” are programs too, so don’t load too many of these into your machine. Remember that “programs” aren’t limited to just the larger ones such as MS Word, Excel or Quake II. Everyone with Windows 95 should be familiar with the System Tray, or “Systray”. This is the small indented region at the righthand edge of the taskbar. Typically, it will include the clock plus various other utilities such as a volume control (for the soundcard) and the System Agent from the MS Windows 95 Plus! pack. Now the trouble is that in the hands of some gadget freaks, it also becomes the home for all sorts of other programs. Each of these might not amount to much on their own but System Agent, which comes with the “Microsoft Plus!” pack, lets you schedule regular hard disc maintenance activities so that they run automatically at certain times or when the machine has not been used for some time. taken together, they can easily gobble up enough resources to make your system slow or unstable. DOS users should note that TSR programs or popup pro­grams amount to the same thing as Systray widgets, so go easy on them. Run too many and they will cause problems. (3). Follow on-screen prompts carefully when installing software. Be sure to let the system reboot when called for, to ensure that critical system files are installed. That’s because some files that are a part of the installa­tion are not ac- tually installed unless the system is rebooted. These are generally dll and vxd files that cannot be changed while Windows is actually running. (4). Install only one program at a time and check that it works correctly before attempting another installation. Installing lots of programs without checking each installation as you go can make troubleshooting more difficult later on if you strike problems. (5). Regularly run ScanDisk. Windows 95 users will find that there are two versions: Scandskw.exe (the Windows version) and Scandisk.exe (the “DOS” version). The Windows version should be used for routine checks (see panel) and it must be run from within Windows 95 (click Start, Programs, Accessories, System Tools, ScanDisk). (6). Run Defrag on a regular basis. This utility “defragments” your hard disk, speeding up access to your files and making the system more reliable. Windows 95 users can run the Defrag utility by clicking Start, Programs, Accessories, System Tools, Defrag. Users who have older DOS 6.x systems will need to exit Windows 3.x com­ pletely before running Defrag. Simply type Defrag at the DOS prompt to run it, or add /? for any program options (ie, Defrag /?). Setting ScanDisk To Run Automatically If a PC is often used by children or by someone who doesn’t know a lot about computers, it’s a good idea to set the system up so that ScanDisk runs automatically each time the machine is booted. For Windows 95, you do that by adding Scan­dskw.exe to the Start­up group, as follows: (1) right-click the Start button, click Open, dou­ble-click Programs, then double-click the StartUp Folder. (2) Click the File Menu (at the top), click New, then click short­cut. (3) In the box provided, type scan­ dskw.exe /a /n (4) Click Next and in the next box type Scandisk, then click the Finish button. The parameters for Scandskw. exe are: /a   to check all ordinary hard disks in your PC, /n   to start and close ScanDisk automatically (no keypresses need­ed), /p   to stop ScanDisk from automatically correcting any errors it finds. Don’t use the DOS version of ScanDisk (Scan­ disk.exe) to routinely scan for (and fix) errors on a Windows 95 machine and don’t place it into autoexec.bat. Scan­ disk.exe doesn’t recognise long filenames. If you do use it to fix errors on a Win95 machine, any long file names associated with problem files will be lost. Theres one more wrinkle here: Windows 95 OSR2 will automatically run Scan­disk.exe when the machine is rebooting after a system crash. It’s usually a good idea to let it fix any problems here before going into Windows 95, after which you should then also run the Windows version of ScanDisk (click Start, Programs, Accessories, System Tools, ScanDisk). Any files with truncated filenames can then be renamed, if necessary. On the other hand, Scandisk.exe can (and should) be used to routinely fix errors on DOS and Windows 3.1x machines. If you want it to run auto­matical­ly at bootup, just add the following line to the auto­exec.bat file: scandisk /all/autofix/nosummary/ nosave This will do an automatic test of the directory structure of all hard disk drives (no surface test), fix any errors that are found, and not bother saving any lost clusters – all this without you having to press any keys or respond to questions. Alternatively, you might like to leave the /nosave option off if you wish to be prompted to choose whether or not to save any lost information. Any “lost clusters” (file fragments) will be saved as files FILE0001.CHK, FILE0002.CHK and so on. It’s then up to you to determine what these are and recover any useful data. May 1998  17 Check the power supply and I/O cable connections if one of your drives fails to respond properly. Faulty lead crimping inside power supply connectors (especially Y connectors) is a common problem, so don’t take these for granted. (7). Windows 95 users should buy the Plus! pack. This handy pack­age has a scheduling program called System Agent, or “Sage” for short. What does it do? Well, it automatically checks your system according to a pre-programmed schedule (you set this) and au­tomatically runs the Scan­Disk and defrag utilities according to this schedule or when you haven’t used the computer for some time. It will also warn you if your hard disc drive is running short on space. If your hard disc fills up, there will be no room for the temporary files that Windows sets up, print jobs will no longer print and your system will grind to a halt or run extremely slowly. The Plus! pack is worth the extra dollars. In my own work situation, I have found that System Agent can dramatically reduce downtime, costs and support calls to a help desk when introduced to a system. (8). Extra RAM will help make your system faster and more stable. Going from 8Mb to 16Mb or from 16Mb to 32Mb can increase the effective speed of a PC by 50-100%. (9). Never ever use old drivers or utilities. Some people install Windows 3.x drivers for printers, video cards and so on when they should be using 18  Silicon Chip Windows 95 drivers. Often, the correct drivers will be on the Windows 95 CD-ROM so don’t make the mistake of installing any Windows 3.1x drivers that may have been included on a diskette with the device. If you don’t have the correct Windows 95 drivers, either contact the device manufacturer or download new drivers from their website. Older Windows 3.x drivers (or worse, DOS drivers) can slow your system down to half normal speed or less, as they were rarely designed for 32-bit access. These older drivers should only be used for DOS/Windows 3.x systems or in DOS mode under Windows 95. Hardware problems If a problem occurs immediately after you have installed some new hardware, then exit from the operating system, switch off, remove the new hardware and see if you can restart the sys­tem. If the system works, carefully replace the item and check your connections. This might seem a little obvious but incorrect connections are often all that is wrong. Be sure to check that all plug-in cards are correctly seated in their slots. Sometimes, a new card might not fit too well, or might not line up with the backplane correctly. Check the physical placement of the card with respect to the motherboard and case. One of the most common problems is a card that is sitting too high in its slot on the motherboard but cannot be pushed down any further because of interference with some other part or with the back panel. If a hard disc drive, CD-ROM drive or floppy drive appears to be dead, check its power connector. The connector may have come loose or you may have left it off when adding new hardware. Don’t take the integrity of power connectors for granted either. Incorrectly crimped leads inside power connectors (especially in Y-connectors) are a common problem. Finally, if you strike hardware problems, think about the last thing you did. It’s all too easy to come to grief by doing too many things at once and then not knowing what was responsi­ble. If you need to add, say, an extra hard disc drive, a new sound card and an internal modem, it’s best to do it one device at a time. Always make sure that each new device works correctly before adding the next. If you’ve added a few extra items of hardware all at once, remove all but one of them. The less new bits to worry about when debugging the SC better.