My Sony laptop shuts down when I connect to the Internet

Every time I try to get on the Internet (wi-fi) my laptop (Sony VAIO windows 7) closes all windows (within probably 3 or less minutes) and begins logging off and shutting down like a computer normally would and then goes into a start up loop unless you turn off the Internet access. Any suggestions? Regrettably those that don't involve setting it back to factory defaults? My computer works okay otherwise. It has a few quirks but I can deal with them.
This is just exceedingly difficult to deal with.

Cordially yours,

C.G.