I'm not sure if you got this sorted or not, we were having the same issue. For some of the affected machines, we just ran a windows update and it fixed it, for others that didn't work.
The final fix that we found worked, went as follows:
Deleted the '%program files%\sims' directory.
Run SIMSInfrastructureSetup.EXE
Run SIMSApplicationSetup.exe
Then run sims from the start menu
It will update manuals and ampark
We were then able to runs sims.net as normal.
We've now done this on all the problematic machines and it's sorted. I don't know why it works, I don't have the time to find out why it works, but it sorted the problem for us.
