Windows 7: Windows explorer crashes (and restarts) on system start-up.

Hi. Today morning I started my PC and just after the start up Windows Explorer crashed and restarted and then did (and does) the same every 10-15 seconds. I googled the problem and did following steps (not in the same order as below) which didn't resolve the issue:



- restarted few times and switched off PC completely;
- tried to fix registry with Vit Registry Fix;
- did SFC /SCANNOW and it finished with information that some issues couldn't be fixed;
- ran Malwerbytes with no malware found;
- did a full Kaspersky Internet Security scan with no viruses found;
- did a clean boot (all non-windows services were not used) and it still crashed;
- did a diagnostic start up (so only basic windows services were used) and it helped;
- I wanted to do a system restore but Windows doesn't have data on any restores, meaning I probably haven't started the service (doesn't it make it automatically?);

Other info:
- system works fine in Safe Mode and diagnostic start up, thus eliminating issue with external applications;
- when in normal mode and crashing I looked at processes appearing and disappearing and found out that at the crash process the file dllhost.exe disappears then and shortly after appears back (it may or may not be relevant);
- I didn't do any major updates yesterday (only updated Steam platform and installed one new game);
- I can't do perfmon /report as in Safe mode it doesn't display anything and in normal mode I don't have enough time to start the application before windows explorer crashes again;
- BSOD Dump & System File Collection is done (attached) and I did it in normal mode (so when system was crashing as it may include some extra info);

I will appreciate any help in that matter as I'm now left clueless to the issue and don't really want to reinstall the system.

My system: Windows 7 Home Premium SP1 x64. Intel i7 920 2.66GHz, 6GB RAM.

Just an update - based on my experience with "fixing" the system, I've decided to back up the data and make a fresh installation (no point in loosing more time on trying to resolve the issue but just spend the time on new system and at least enjoy a faster Windows for some time). Funny though that a year ago I had to do the same due to some dll corrupt file (it was much worse then). I really love Microsoft!

P.S. Thanks for reading this thread, if you think you may add something (so in the future if someone looks for info on how to fix it) feel free to add some advice.

The problems likely do not stem from Windows but from the following software:

Many of us on the forums actually do not recommend automated optimization tools for Windows 7. Windows 7 does a much better job of handling its own optimization than its predecessors did. We especially do not recommend registry cleaning as an "optimization" step because automated registry cleaning causes more harm to the registry than it actually repairs.

In the future, if you need help optimizing Windows 7, please post a thread in Performance & Maintenance - Windows 7 Forums or follow the tutorial enclosed in that forum to Optimize Windows 7.

Thanks for that but Vitsoft can't be an issue as I installed it after experiencing the problem (in fact did some other steps to resolve is first).

I will however keep in mind your tip (in fact I tried not to use that software if not really necessary). Some time ago I had different optimization application but that was longer time so I don't think it related with the above issue.