visual studio express 2012 web cannot connect to Microsoft® SQL Server® 2012 Express

Question

is there any bug when connecting visual studio express 2012 web that is installed on windows 7 to connect to SQL Server Express 2012 or 2008R2?

the error message is this:

> A network-related or instance-specific error occurred while
> establishing a connection to SQL Server. The server was not found or
> is not accessible. Verify that the instance name is correct and that
> SQL Server name is configured to allow remote connections. (provider:
> SQL Network Interfaces, error: 26 - Error Locating Server/Instance
> Specified.)

in my situation, VS connects to SQL only if from server OS to Server OS

or it is from win7 OS to win7 OS ?

here is the scenario I got in my environment : we have 4 machines

1-win2012Srv: -Virtual machine -windows 2012 serverSQL Server Express 2012 visual studio express 2012 web -Symantec antivirus (disabled) -firewall is disabled -Static IP address

2- win08r2srv: -Virtual machine -windows 2008 R2 server -SQL Express 2008 R2 -visual studio express 2012 web -no antivirus -firewall is disabled -Static IP address

3- Win7PC1: -Real machine (PC) -windows 7 -SQL Express 2012 -visual studio express 2012 web -Avast antivirus (removed already) -firewall is disabled -Dynamic IP address

4- Win7PC2: -Real machine (PC) -windows 7 -visual studio express 2012 web -Avast antivirus (Running) -firewall is disabled -Dynamic IP address

the result is:

> Legend :) 
> 
> VS = visual studio express 2012 web
> --> = connect (i.e. I can connect to the SQL Server database)
> X--> = cannot connect (i.e. cannot add database connection)

vs on win2012Srv --> SQL on win08r2srv

vs on win08r2srv --> SQL on win2012Srv

vs on Win7PC1 X--> SQL on win2012Srv

vs on Win7PC1 X--> SQL on win08r2srv

vs on Win7PC2 X--> SQL on win2012Srv

vs on Win7PC2 X--> SQL on win08r2srv

vs on Win7PC2 ---> SQL on Win7PC1

thanks

Hasan

Answer 1

I really appreciate your valuable inputs. My hair about to fall because of this problem :(

Tom, thanks, I have gone through that article weeks ago, but no luck :)

The Summary:

I have made a work around to resolve my problem. I have created a new virtual server on the second physical DELL server (with SQL Express 2012).

The problem seems to be a network issue on the hyper-V virtual switch!!

More details:

As described previously, VS connects to SQL service within the same Hyper-V only, although all configuration are right. From any PC within my domain, I can connect to the SQL server on the first Hyper-V service using the ODBC or the connection string file (.UDL), BUT not through the “visual studio express 2012 web” !!!!!!!!!

Now, I can connect from any PC (using visual studio express 2012 web) to any SQL server Express 2012 on the second Hyper-V .

I have made 4 virtual service on the first hyperV and 4 on the second HyperV. All with the same result:

• •VS on PC's can connect normally to any SQL server on the second HyperV•VS on PC's can NOT connect to any SQL server on the first HyperV

• •VS on virtual servers on first HyperV can connect normally to any SQL server on the same physical machine/Same hyperV .

• •VS on virtual servers on first HyperV can connect normally to any SQL server on the second physical machine/Second hyperV .

• •VS on virtual servers on the second HyperV can connect to any SQL server on PC's or on the second HyperV/Same physical machine.

• •VS on virtual servers on the second HyperV can NOT connect SQL servers on the first HyperV

Long story that last more than one month :(