Windows ME

I am running Windows ME on a Dell computer and have been getting a lot of: An error has occured. To continue…….. Followed by File Name: VCACHE (01). The message tells me to CTL,ALT,DEL to continue, but nothing helps short of powering off thecomputer. I did check the way CACHE was configured and set the configuration to “Let Windows calculate and determine cache needs”. I have added memory to 256 MB with no help. Can the problem be HD failure? or Windows ME?
Any help will be appreciated.