Hi,
Try on a Clean Profile.
If happens then it would need to be reported, if not, you have to check your Profile settings or set up a new one if the source problem can't be found.
Once working again, do weekly back ups.
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If a new Profile is needed:
You could try pasting some files to the new one from the old one - look at the Signature -.
Paste old files could repeat the same problem.
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"Off Topic Tip"
Follow the Signature's Backup | Reset link.
Take the opportunity to start a Backup plan and even create a Template Profile.
SyncBack | Synkron helps.
Windows 7 (x64)
Opera Test profile | Back up | Reset