Event ID: 2022
The server was unable to find a free connection xxx times in the last 60 seconds…
There is a registry change available to increase the number of connections… But this is just a work around. It doesn’t solve the problem that there is some service (probably) that is contacting AD too much and effectively doing an unintended DOS attack on your AD servers.
Probably this is caused by some setting on your workstations (possibly a GPO setting) that is telling the workstations to contact AD at a particular time.
For me, I fixed Event 2022: The Server Was Unable To Find A Free Connection by changing my App-V settings. App-V was set to refresh the publishing every hour. I changed the GPO to only refresh on logon so all the PCs weren’t refreshing all at the same time.