SSPI handshake failed with error code 0x80090308, state 14

Problem

You cannot login to SQL Server, and see the following error in the logs:

SSPI handshake failed with error code 0x80090308, state 14 while establishing a connection with integrated security; the connection has been closed. Reason: AcceptSecurityContext failed. The Windows error code indicates the cause of failure.  [CLIENT: [IP ADDRESS]].

Solution

There can be several reasons for this error, so rather than listing them all, read the following useful links:

--Show details of all connections
select auth_scheme, * from sys.dm_exec_connections