When using replication, the Publisher and Subscriber need to be able to communicate with each other. If they cannot, the following message can appear.
"A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and the SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)."
There are a number of possible causes...
- Maybe the firewall is blocking either the port used by the SQL instance (by default, this should be dymanic) or the SQL discovery service (Using Ports TCP 1433 and UDP 1434). http://support.microsoft.com/kb/287932
- SQL may not be configured to allow TCP access (Rectify in SQL Server Configuration manager>SQL Server Network Configuration>Protocols for AUTODESKVAULT)
- There may be a physical network problem
- Domain trust issues with Agent accounts http://support.microsoft.com/kb/160563