Me too. I get these errors on Windows 7 all the time (at least a 3-4 times a day). I run TOS 4.2.3.r67267 on Wind 7. I restart the TOS and then I am able to work without the error for some time. Then it happens again. Annoying. Seems to happen more often when I need to kill a frozen job.
After having this same issue I realized that it was only happening on one of the jobs that I had built. The culprit in my case was a foreign key constraint failure. When I rebuilt the job from scratch I had the same issue until I fixed this issue. For whatever reason it wasn't showing as a foreign key constrain failure like it usually does, but this seemed to fix it.
This may not be your issue but worth a check..
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