On (at least) three network we manage, users complain about the same thing:
Randomly, between three to ten times per day, Explorer is frozen. This happens when either opening an Office document, attaching a document to an email, opening Windows Explorer to access mapped drives, ...
When it occurs, all users in that same network are blocked at the same time. It lasts for 10 seconds roughly and it goes back to normal. No errors on the server, no errors on the clients, no errors on the switches.
Environment is roughly the same across these three networks: Windows 2012R2 on ESXi (some are 5.5 some are 6.0), firewall is SonicWALL TZ series, switch is managed on one network, unmanaged on two, folder redirection is ON (we tried with OFF, no change).
We tried with or without Antivirus (BitDefender), with or without folder redirection, with or without DHCP... We tried moving the datastore to another array of disks. We tried adding RAM to the VM Host.
Last change was DISABLE "Domain member: Digitally encrypt or sign secure channel data (always)" in the Default Domain Controller policy, no change.
Any idea ?