Hi guys, I know there's hundreds of topic about this error out there, but not a single one seems to apply to my specific situation.
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 that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)
We have three branches, 1 head office and two satellite branches. Our in-house developed application connects to a SQL Server 2005 instance running on a server with a live IP which the branches connect through and a local IP that the head office connects through i.e. app at branches connect through <live IP>\<instance name> and the head office connects through <local IP>\<instance name>. The application is exactly the same across all three branches except for the connection string used...it's exactly the same for both satellite branches though.
Head office has no problems connecting with the application. Branch A has no problems either. Branch B however does. Branch B's network is setup as follows...ADSL connection into a wireless/wired router that each user then gets internet access through. If anyone in Branch B connects to the internet through 3G or their cellphones on their PCs, then the application works. But not through the ADSL setup. However, to make it more interesting...one of the guys made an initial connection to the internet using his cellphone as the modem and successfully logged into the application...he then disconnected the internet from his cellphone and connected through a cable connection to the ADSL router and successfully managed to carry on utilising the application, performing actions that would have performed SQL queries to the server...and all ran successfully. But then he closed the app and opened it again (cable to router connection) and again login failed.
Please any ideas.