I have had this problem twice now with last two updates for Windows 7 and researching the Opera Forums I found one solution that WORKS, and improvised to find another.
OPTION 1 - The first is using the Windows Safe mode, this definitely works jut you loose browser history.
- Press Windows Key + r
- Go to boot and select safe mode (After your PC restarts it will be in Safe Mode)
- Open Opera
- Clear Browsing history
- Use steps 1 to 2 to open msconfig
- Unselect Safe mode and restart
OPTION 2 - WebData
The second I stumbled upon while looking for alternatives, so I have typed it up as a Blog post so I can update and improve over the next few days if I get problems when updating the other PC's (windows 7 and 10) in our office....
(Fingers crossed thats a NO...)
Hope this helps ..