EXPLORER.EXE

Hello,

Pls of recent, anytime my system boots up, on the desktop an error message comes up and says EXPLORER.EXE cannot be started and it will request to send an error report or not to send it. I checked my start up registry and found out that it was enabled to run and if I disable it upon system restart, it enables itself again.
I also checked at my task manager and found out that it takes up reasonable amount of memory and I also see explorer.exe also displayed.
I actually suspect without doubt that it is a worm and I actually need your help in trying to resolve the issue. Thank you very much