Open the file SYSTEM.INI with notepad.  It is found in your Windows directory. 

Locate the [vcache] section, and create following two lines if they aren't already present.

MinFileCache=0
MaxFileCache=4096

These numbers can be tweaked to suit your needs.  These numbers are the amount of memory in kb that will be used for caching.  MinFileCache should always be set at "0" while MaxFileCache should be set at about 25% of your current memory.  For example, if you have 128mb of memory, try setting this number to 32768.  

This requires a reboot.

If you receive this message:

Error: An I/O subsystem driver failed to load.

Increase the MaxFileCache to 6144. 

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