I just ran the recommended upgrade (monero-gui-install-win-x64-v0.18.1.2) and now Daemon will not start. I can't start monerod.exe either - it just launches and disappears. So I don't know how to get the program working again or to get access to my wallet. The files haven't been quarantined by my antivirus and all monero .exe files are on the exception list.
OK, just thought I'd post this in case anyone else had the same problem – uninstalling and re-installing did nothing, doing a system restore did nothing – but somewhere I read someone saying that stopping the program, deleting the IMBG folder within the hidden folder (
C:\ProgramData\bitmonero\lmdb), and then restarting the program was the solution. IT WAS! FINALLY it's working again!
I hope that this helps anyone else – there must be many more people affected.