Out of the blue, explorer.exe crashes without auto-recovery, what's the problem?

Question

Windows

Good day, with you I am a generator of questions and my next problem.
explorer.exe crashes, just crashes, no errors, no error windows, no logs, and no traces at all, on 4 different computers, on the same network. There are 14 computers in total on this network.
What was tried: Reinstalling Windows (clean enterprise), checking software (piece-by-piece installation on problem machines and monitoring reactions), checking the router (for outside interference), iron tests (for wear, errors, overheating) , checking for viruses with all kinds of software, registry control and autorun.
After many manipulations and attempts, the computers stopped kicking out. We thought that everything was fine and the problem was solved, but the next day, 2 and 4 computers were knocked out anyway. Along the way, 3 more computers were reset. That is, in fact, we have 7 computers that are identical in terms of filling and software (directly 1 in 1), but only 2 of them suffer from the phantom blade explorer.exe. Computers are ordinary office computers, far from weak. Soft - office package 2010, skype, google chrome, firewood from the disk mat. boards, binding to a shared folder, configured mstsc (1 pc.), adobe acrobat pro, VNS. And there is another oddity in the fact that it falls between 8 am and 7 pm, every hour, starting from the first fall. Also, if it falls off, then it falls off for all the problematic ones, so it was and still is. Falls off with a delay of 2-8 seconds. We looked at a lot of things, but we did not manage to find the problem until the end.

Answer 1

> explorer.exe crashes, just crashes, no errors, no error windows, no logs, and no traces at all, on 4 different computers, on the same network.
At least there should be an entry in the system log if optimizations were not disabled.
> Reinstallation of Windows (clean enterprise)
And updated to the current state via WU / WSUS?

Answer 2

strange combination: windows (pure enterprise) and office 2010 package

Answer 3

Is there a domain? Do many people have access to admin accounts?
Are local admin passwords the same for everyone?
maybe someone over the network runs a script.
check for PsExec64.exe/PsExec.exe on computers