Can't build for win64, access violation error in module buildsystem.exe


i get the following error when trying to build for win64 shipping or development_editor, win32 shipping works.

1> --------------------Build System Error-----------------------------------------
1>EXEC : Fatal error :
1> Task queue management failed.
1> Error starting Task ‘cl: Task: Default->Action3 (Tool3)’ on machine ‘Local CPU 1’
1> Failed to associate 64bit module at 0x7FFAA6BC0000
1> Failed to associate function ‘NtQueryFullAttributesFile’ at 0xA6C547D0
1> Access violation at address 000C1953 in module ‘BuildSystem.exe’. Write of address 00000000
1> -------------------------------------------------------------------------------

Thanks for the help.