P365: - The password sync is not working - "Write: The operation has timed out" (4328658)

We noticed our password sync stopped working. We see the following error, what is causing this?

Write: The operation has timed out. "System.TimeoutException: The operation has timed out. at System.IO.Pipes.NamedPipeClientStream.Connect(Int32 timeout) at CDS.ADLibrary.PasswordSync.PasswordClient.IssueRequest(String request, Nullable`1 timeout) at CDS.ADLibrary.PasswordSync.PasswordClient.Noop(Nullable`1 timeout) at CDS.ADLibrary.PasswordSync.PasswordService.Start() at CDS.ADLibrary.PasswordSync.PasswordHelper.#nyb() at CDS.ADLibrary.PasswordSync.PasswordHelper.SetPassword(String sAMAccountName, String hash) at CDS.Model.ActiveDirectory.SetPasswordHashes(SearchResultEntry entry, String passwordHashes) at CDS.Model.ActiveDirectory.UpdateObject(String objectId, ICollection`1 changes) at CDS.Model.UpdateJob.ApplyChanges(IWebServiceFactory webServiceFactory) at CDS.Model.UpdateJob.Run(IWebServiceFactory webServiceFactory, CancellationToken cancellationToken) at CDS.Model.Job.Execute(IWebServiceFactory webServiceFactory, CancellationToken cancellationToken)"

UPDATE: A Windows Defender March 2021 update causing issues with Password Syncs

For Sophos: Disable Credential Guard to resolve Password Sync

Sophos is one of the difficult AV products we deal with for allowing password reads.  We found with Sophos to fix this and a component piece of Sophos called Hitman Pro which is a real-time protection service causing the issue.

Instructions from Sophos on disabling HitmanPro:

1. Stop HitmanPro.Alert service
2. Navigate to "C:\Windows\System32\"
3. Rename hmpalert.dll to hmpalert.orig
4. Navigate to "C:\Windows\SysWOW64\"
5. Rename hmpalert.dll to hmpalert.orig
6. Reboot the endpoint (after reboot HMPA driver will not load)
7. Check/Stop HitmanPro.Alert service as needed

Carbon Black Defender can also be very aggressive, and must be uninstalled.until the migration project is complete.