"Out of environment space" MS-DOS error

What gives?
I'm in a Dos shell and some environment variables are set. I try to add to the PATH variable and I get "Out of environment space" when the PATH is kind of long. If I set only this new PATH that I was trying to append, it works without any error. I just recently began running into this problem because I used to set (add to) the PATH in this way before successfully.

Sure I've been freely installing more software to the hard drive, but I have 80MB of RAM and would love to have Windows actually use it! I've had the 80MB for years.

If I set some of the existing environment variables to an empty string "set aVar=", then I can add more environment variables before I get the dreaded "Out of environment space" error.

At work I've seen a **** load of environment variables set, so I suppose I need to tell Windows to actually use the memory that it knows I have (by the "mem" command and at bootup).

Please advise.

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Actually, let's see if this works http://support.microsoft.com/support...SRCH&SPR=MSDOS
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As I recall enviroment varibles such as the PATH resides in the 640K of conventionel memory, and can't use your 80 MB of extended memory.

So it's back to the good old optimizing of the devices and drivers that you load in your autoexec.bat and config.sys. The golden rule it, erase whatever is related to DOS, like soundcard drivers for DOS and mousedrivers.

I used to be pretty good at tweaking DOS to load in the most whitout usin all the memory, but it's been 6 years since I last did that, so I'm sorry I can't give you any more help than this.