|Since the app is the only issue, this does not fit into what you would see if being hacked. A hacker would have left the program up but redirected financial payments to themselves.|
Sounds more like the application is crashing. You should see errors relating to this in the application event viewer log.
Make sure you are maintaining the health of this workstatation with regular updates and maintenance [disk cleanup/defrag, malware/AV scans, etc]
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