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Errors - Operational Errors

 

You will at some time receive the following message:

"This program has performed an illegal operation and will be shut down"

On the window which bears this message there will be 2 buttons, Close and Details.

Before clicking the Close button, first click the Details button.

Many errors occur when one program causes a fault in another program or library file where it is the 2nd program which is at fault eg:

Explorer caused a page fault in Winnet.dll

This tells you that Explorer is not at fault but there may be corruption to Winnet.dll

Rather than re-install the whole of Windows again just to fix this fault, simply go to another PC (with the same operating system eg: Win95, or Win98..etc).

Use File Find (or F3) to locate the file (e.g: locate winnet.dll in this example). Note where the file was found (e.g: in Windows\System in this example).

Copy this file to floppy (or across a network) and then into the corresponding folder of the original PC (e.g: copy from A drive to C:\windows\system, in this example).

Note: If the file to be copied on to the original PC is one currently in use by Windows, then re-start the PC in DOS mode, then use the Copy command at the A:> prompt e.g:

A:> Copy Winnet.dll C:\windows\system

In most cases using this procedure will rectify most problems.

If however you are receiving many such errors, frequently and randomly, then using the above method may prove fruitless and then you must look elsewhere for the system faulting - the first is your RAM or SDRAM memory chips (See below) .

 

 

Illegal Operation Errors - bad memory

Whilst an infrequent illegal operation error may be just a 'glitch' and can usually be ignored, you should restart your PC should one occur. However, If your PC is performing these errors:

Then, the most likely cause is a fault in one of the memory modules.

You will need to take all the memory chips out and re-introduce them one by one (DIMM) or in pairs (SIMM). See below:

The SIMM type of memory is fitted into 4 possible slots, in banks of two. The slots are usually white in colour and are usually situated near the power unit. So that you do not mistake the white PCI slots for these, each slot has a clip at either end. A Bank is 2 slots which each slot having the same size of memory.

Example:

Slot 1 - 16MB

Slot 2 - 16MB

Slot 3 - 32MB

Slot 4 - 32MB

Installing/re-installing memory

SIMM memory has 72 gold pins at the card edge and a notch in the middle of the card edge. The notch in the card edge will match a gap in the middle of the slot. At one side of the chip is another notch or cut out which matches a block at one end of the slot where the clip is.

You can easily tell which way round is correct because the card edge middle notch will match exactly the middle gap in the memory slot.

Insert the chip in the center groove of the slot at a 45 degree angle. When you feel that the memory card edge had gone into this grove, push the chip up to a vertical position. You will hear the clips at each side engage with a small clicking or snapping sound. Check each side to ensure each clip is engaged properly. Put a finger on the top edge of the memory card and if there is little or no movement laterally then the memory card is fitted correctly.

Note: slots can take 8MB, 16MB, 32MB or even 64MB (consult your motherboard manual for the maximum amount of memory, but do not mix memory size in the same bank.

DIMM memory has two notches on the card edge and two gaps in the slot. Make sure the memory card is oriented to match the slot. Ease back the two white levers at the ends of the slot. Push the card in vertically until the white levers snap into the cut-outs at each end of the memory card. If the levers are fully in the cut-outs then the memory is fitted correctly. DO NOT USE EXCESSIVE FORCE WHEN PUSHING THE CARD DOWN INTO THE SLOT.

Important experience note:

Before replacing the system unit cover, check that all cables and connectors from the motherboards and to drives etc., are correctly in place. You could have pulled out or partially pulled out a connection whilst trying to get the memory installed. When you are sure all connections and memory is fitted correctly then and only then replace the system cover. This checking only takes a few seconds which is better than having to take the cover back off and start again.

 

 

The DIMM type of memory is fitted into 1 or more possible slots. The slots are usually black in colour. So that you do not mistake any black ISA slots for these, each slot has a white clip at either end.

Usually DIMM memory is not in banks so each slot can have a different memory sized chip in it

Important Notes: