I have a web server which has been working correctly for some months now.
This morning, on adding a new site, a strange issue has started appearing:
Steps:
- Create new site
- Right Click on site, go to Basic Settings -> Connect as -> Set -> Enter account details -> OK -> OK
- Click Test Settings... (all tests pass)
- Click Close -> OK
At this point, all seems normal. However, on going back to Basic Settings -> Test Settings, the tests now fail.
On three of these tests, the account is locked out, as if the password was wrong. This occurs, even if I try with the Domain Admin account I am currently logged in with. Every other site on this server is now showing the same issue with their respective credentials.
The event viewer on my DC is showing up Event ID 4771, Kerberos pre-authentication failed. Failure code is 0x18 which normally means the password is incorrect, but I know it is correct (as I can use it elsewhere) and it does accept the credentials at first.
Extra details which may be relevant:
- Windows Server 2012 R2 Datacenter
- IIS Manager 8.5 .NET 4.6.2
- No shared configuration set.
