I had a same experience that you have.....

many facts makes a Fata Error C0000005

1. DCOM98 install problem ( try to reinstall DCOM98 )
2. SCREEN = OFF in config.fpw problem
3. the time of quit a application.

may be you have in the 3th case.......

On you have this case,
when the time of quit all of your controls must be null~!!!
VFP60 may doesn't cleared within's all controls... when it destroyed.

Especially, Timer make a problem in my case....

good luck!
With Greate regards..