I have had Bitcoin Core on this computer before, and it worked fine for over a year with no trouble. I had recently uninstalled it, and today attempted to re-install, but, after running setup, on attempting to open bitcoin-qt.exe, the following error appears:
Assertion failed! Program: C:\Program Files\Bitcoin\bitcoin-qt.exe File: wallet/scriptpubkeyman.cpp, Line 720 Expression: mapKeys.empty()
...with three options, Abort, Retry, and Ignore. This happens consistently.
I am running bitcoin-0.20.1-win64, Windows 10. I have tried further uninstalling and reinstalling, and installing in both a C:\ and D:\ drive. Running from the command prompt with -rescan does not help either.
Any assistance would be very much appreciated.