mysql upgrade fatal error on Spectrum upgrade, shows no errors in the post install log but the following fatal error is in the mysql log.
Error: Server version (x.x.x-enterprise-commercial-advanced) does not match with the version of the server (x.x.x) with which this program was built/distributed. You can use --skip-version-check to skip this check.
FATAL ERROR: Upgrade failed
This error can be caused for many reasons and is usually environmental such AV running and holding the file in question, or a lag in the OS.
e.g. here the procmon log file shows a problem when deleting/overwriting the $SPECROOT/mysql/bin/mysql.exe file.
We see the DELETE PENDING in the procmon, therefore when the cp command tries to copy the file, the Permission denied error occurs and the new copy of mysql.exe is not written to the bin directory.
Release: Any version of Spectrum running on Windows
Reinstall the current version of Spectrum on top of the current install, after removing the old mysql as follows: