1456 Error creating witness in SQL Server 2008 R2...

Question

Setup is two 2008 R2 Standard servers with a mirrored database. All works fine without a witness - I can perform a manual failover and my test app works off the failover database. Trying to add 2008 R2 Express as a witness to enable automatic failover,
and getting error along the lines of:
The ALTER DATABASE command could not be sent to the remote server instance TCP://%witnesserver.fqdn.com:5022. Error 1456
Found a fairly recent fix for SQL 2008 (r1) for this, but not for R2. Is this still a known problem in R2 or am I missing something crucial?
All the servers use the same service account for all services (it's proof of concept, not production).
Thanks in advance,
Neil

Answer 1

In my case after spending several hours of troubleshooting/Googling, with none of the many posted/documented fixes working, I found the solution to my SQL 1456 error to be ROOTED in the SQL Server Configuration Manager\SQL Server Network configuration\Protocols
for MSSQLSERVER\IP Addresses.  There was an old IP address listed in the (Active) IP1 configuration.  Even though DNS was resolving to the new/correct IPaddress and Witness Name along with the local HOST file on the Pricipal/Mirror/Witness all
containing the correct IP/DNS entries, this old address still was embeded in the SQL Server Configuration Manager\SQL Server Network configuration\Protocols for MSSQLSERVER\IP Addresses.  Once I modified the IP entry to match the current Witness
IP address all was GOLDEN.  This may not be the solution for your 1456 Error, but it is one that can be added to the plethera of possible fixes for it.  I hope this saves someone some time and effort along the way.  - Lou