After a Reboot of a Domain Controller Server 2008r2 I got many Errors Event ID 1030
And as well a Warning event LSA Event ID 40961 ?
The Security System could not establish a secured connection with the server ldap/xxx/xxx. No authentication protocol was available.
After reading on the net, I did several Diagnostics test:
dcdiag /v /c /d /e /s:%dcname% > c:\dcdiag.txt
repadmin /showrepl %dcname% /verbose /all /intersite >c:\repl.txt
May errors appear in there but did not ring a bell to me ?
I also did a machine Pwd reset on the domain controller that had the issue, but not success too
The nltest.exe /dsregdns was OK but did not solve it to ??
After trying all of the above did not help …
But simply restarting the AD Domain Services
It gave a few warnings but after that everything was back to normal.