What does this computer error mean, and how can I make it stop happening?

Every time I restart my PC, I get this error message:

ERROR LOADING C:\PROGRA~\MYWEBS~1\bar\3.bin\M3PLUGIN.DLL
The specified module could not be found.

What the heck is that about? It goes away when I click “OK”, but it’s been happening for months and it’s kind of driving me crazy. Can you tell me how to get rid of it for good?

I’m technologically challenged, so please use little words.