Low virtual memory usually is an indication that the hard drive that contains the swap file(s) is low on free space for virtual memory. It is also an indication of insufficent physical memory. [virtual memory is based upon physical memory size at a default 1.5 times the amount of physical memory]You CAN use a 3rd party utility to increase the amount of free space in the partion provided that there is sufficent space available on the HDD. If not, going to a larger drive might solve your problem.Adding in additional physical memory without sufficent space on the hard drive will not solve a low virtual memory problem, and may cause a low virtual memory problem. If you have added additional physcial memory to your system, but did not change the virtual memory size a "low virtual memory message will appear [usually Windows will recalculate for you but in some cases may not].
Question: What changes were made just prior to this problem, both changes in hardware and software?