Cygwin mintty fails to start, requires Cygwin install finalization to run properly

I have a recurring problem using Cygwin (on a Windows 10 machine with a bunch of corporate spyware/malware which I had to live with). Whenever I install or update Cygwin - everything seems to work fine, and I can start a terminal session. However, if I leave it be for a while - and possibly go through some auto-updates by Microsoft and/or by my employer - it stops working. That is, running: C:\cygwin64\bin\mintty.exe -i /Cygwin-Terminal.ico - has a window come up and immediately terminate itself. Updating cygwin rectifies the problem. I should also mention that, from a regular cmd shell sessio

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