If you are not specifically doing anything that provokes the error, then it must be something running automatically on a schedule.
It's a Windows error response, indicating that it is something running on a command line.
It's wrapped in an MC skin, suggesting it is being run from within MC.
Check the MC scheduler, which can be found in the tree under "Services and Plugins".
If it's not there, the only other place I could imagine it being is in your auto import settings, in the "Tag on Import" rules for one of the folders there, though feel that this is unlikely.
Other than that, I'm all out of ideas. Sorry.
