Hi
Can anyone tell me why my computer keeps coming up with a sign - vitual memory very low , windows is increasing, why is it very low and what can i do about it please.
is it anything to do with the ram as i think that is low also- (computer is 6 years old .)
but still working !
appreciate any replies.

Virtual memory is the space set aside on your hard drive where Windows stores things to transfer in and out of the RAM.
More RAM would be a plus [very cheap now, if you can find what your computer requires-6 years is an eternity in the computer world].  
The hard drive available space may be getting tight, that's why you keep getting the message. A larger drive or a second drive would alleviate that problem.

   Another reason is that you may have too many programs open.  The more programs you keep open, the more virtual memory is needed.  A temporary fix may be to close programs when you are not using them, but you should look into the things that dlwolff0 suggests above as more permanent fixes.

Another possibility for a temporary soluction, until you make the hardware changes suggested by dlwolff and Ray:

If it happens when your machine's been on for a while, it's probably a memory leak.  In other words, a program is using memory and not returning it when it should.  This is very common.  For example, I often get that message if I leave a document open too long in Foxit Reader 3.0.

The temporary solution is to pay attention to which programs are doing it, and to close them immediately when you're finished with them.  Don't leave them open out of habit or laziness.

Good luck.
C.