I've run into this with registry cleaners, virus and trojan damage. The thing is that repair is not a sure thing. I'll try the methods you tried but the damage can run deep or the infection is a root kit which makes it simpler to reload from backup or start over. This, when it happens can drive home the fact that you can't go without backups with Windows.
To me unknown reason Explorer in windows7_64ultimate stuck in such a way that I don't know what to do with it.
After turning on the PC and desktop appearance boots after some seconds Explorer will switch on and off - ie all the icons and a desktop background flash, and cannot run any program. The mouse is slow, delayed response.
I tried all my available options: scf/ scannow - everything is ok, last know good configuration. Further system restore to its previous state program, which I suspect is in on it (utility mkvtoolnix for basic video editing). It was the latest software that I installed (although then uninstalled). The virus probably will not, maybe malware? How can I find out if it is?
This question I am writing in safe mode, which fortunately allow basic use. I cannot reveal here any resident programs on background with RSIT.
I want to avoid, if possible, os reinstall. Before that, I ask here if anyone has similar experience and possibly advise perhaps trivial procedure. Like this one, which just doesn't work:
http://answers.microsoft.com/en-us/windows/forum/windows_7-performance/windows-explorer-in-windows-7-keeps-crashing-and/c6fddc14-7649-4334-ac9a-6d049fd503bd?auth=1
Thanks for any response
Peter

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