When I opened an file through worldbuilder from my desktop and later on moved this folder/file.
I got an exceptional error when restarting my Worldbuilder.
The reason for this to occur is simply because of the "recently opened" feature inside worldbuilder it can't find the file and triggers the error.
The error message:
EXCEPTION_ACCESS_VIOLATION: The thread tried to read from or write to a virtual address for which it does not have the appropriate access. Access address 0x0022a253 was read from. Exception occured at 7c34fedc MSVCR71.dll+0xfedc, setvbuf+0x73a.
1. Start > run > Regedit
2. Ctrl + F > worldbuilder
3. Worldbuilder > Recent File List
4. Removed all except for the first default one (Default) REG_SZ (Value not set)
When done properly you can now startup worldbuilder.
(Most people resolved this issue by simply reinstalling the game)