I get the same thing. So I checked my event logs. I get 0xc0000005 error,
To figure out what this is, you drop the 'c' and plug it into net helpmsg.
This is what I got
C:\Users\thisisme>net helpmsg 5
Access is denied.
So for weeks I tried to think of what it is trying to access. I kept thinking
Vista updated itself and caused the problem with a new version. I think this is
partially correct as it did not happen till a while after I installed 2.6.6
Finally, it hit me. Vista gives you grief when you access some parts
of the c:\documents and settings folder. So I right-clicked on the
gimp-2.6.exe file and said run as administrator.
This worked moments ago so I am unsure as to the permanency of
the work around. I am posting in the hopes that the developers will
see this and correct it on their end
Gimp-user mailing list