Why can't I open LO files from explorer after resume from hibernation?

Somehow I sometimes can’t open LO files from Windows Explorer after resuming from hibernation?
I still can launch PDF, JPG, etc in the same way.

FYI, when I click on an ODT or ODS, the hourglass appears for a few secs, then nothing. It’s as if Windows has sent the instruction to LO, but LO doesn’t get it.

I can still open files from LO itself though.

LO4.4.0.3 in Windows 7

I would reset my user profile. For details please refer to: https://wiki.documentfoundation.org/UserProfile

Meaning lose my settings? If so, I don’t want to do that.

I should add that the problem goes away upon restart. So, I suppose it can’t be a profile problem. It can happen again though when I resume from hibernation again. But maybe not, since I’ve reverted to due to some (for me) regression bugs I’m not willing to tolerate. Since then the problem hasn’t happened.