Problem:
You are trying to setup a mirroring on a Database called xxxDB(SQL server 2012).
You are getting this error while trying to setup mirroring.
“Neither the partner nor the witness server instance for database “xxxDB” is available. Reissue the command when at least one of the instances becomes available. (Microsoft SQL Server, Error: 1431)”
Cause:
This can happen if the mirroring breaks.The principal server is not configured for mirroring any more , but the mirror server still thinks that he is the mirror partner. The state of the Mirror server is “Disconnected”.
Solution:
At the Mirror server open Microsoft SQL Managment Studio , and run the command
ALTER DATABASE “DBNAME” SET PARTNER OFF
This will remove the mirroring partnership from the mirror server.
Then run the mirroring wizard again , on the principal server.