As unbelievable as it sounds, Microsoft really didn't anticipate the current structure with computers and users going beyond the 528 Megabyte limit on RAM or 16 MB on Video RAM.  They made provisions so that it would be possible to install it, but left a loophole, so that the operating system couldn't handle it.

You probably get "Fatal Exception" errors quoting some memory address and a "VCACHE" conflict.  Or maybe you realized you can't get an MS-DOS prompt to run.

Believe it or not it is all related.  As we understand it, the variants of the WINDOWS operating systems address RAM in the MSDOS memory partition.  When you have more than 528 Megs of RAM it takes too much memory in the MSDOS area to keep track of all of the addresses and to run a MS-DOS program.  It turns out a lot of the current software available for those operating systems run MSDOS programs in the background.  These programs wont run in this situation.  As a result the software just wont function properly and you see a lot of lock-ups and exception errors. 

THE GOOD NEWS!  It's really easy to fix.  According to Microsoft, you can regulate how much RAM will be addressable in the vcache right in the SYSTEM.INI file.  

Use "notepad" to open the C:\WINDOWS\SYSTEM.INI file.  You will probably have to specify the files name directly since by default, notepad only displays text files.

Look for the following fragment of lines:

Make it read exactly as follows:

Save the file and reboot your machine and you should be on your way to a better computer experience.  

By doing so, you will minimize the amount of RAM addressed in the VCACHE.  Don't worry you will still have access to the remainder of your RAM.  

I was averaging 20 reboots a day before making this change.  After the fix, I have yet to have my system crash.  Best of all I've got my MSDOS prompt back.

This problem can result in bad DNS issues in Internet Explorer and email software.  Also programs like MS MONEY which uses MS PASSPORT can also cause systems to crash which have not made this change.

As a side note.  once you've made this change and your system is running more smoothly, we recommend that you go to Microsoft's "WINDOWS UPDATE" website and download the critical updates.  It is worth the 5 Meg to 10 Meg download to patch up all of the potential security holes, especially if you use Outlook Express and any browser based financial software that uses a messenger program in the background.

Disclaimer : This hack may result in adverse side effects to your system operation.  If we had experienced any, we would list them here.  But we haven't and we strongly recommend this hack even for computers with less than 528 megs of RAM.