Unable to connect to SQL Express "Error: 26-Error Locating Server/Instance Specified)

Question

I am at an loose end with one particular box that is running SQL Server 2008 R2 Express.

• Windows Firewall is configured to allow inbound TCP & UDP 1433, 14

Answer 1

If you have done anything but in spite of all couldn't connecting?!! In my case i have changed connection part splitting port "," instead of this ":"

The corresponding TCP port or pipe name is not specified in the connection string (such as Srv1\SQL2008, 1433).

Answer 2

Go to SQL Server Configuration Manager > SQL Server Services > In Right Side window show all the servers which may stop. If you are using "SQLEXPRESS" then , Right click on SQL Server(SQLEXPRESS) and start. After try to connect server... I had same problem but I resolved by these steps.

Answer 3

All you need to do is to go to the control panel > Computer Management > Services and manually start the SQL express or SQL server. It worked for me.

Good luck.

Answer 4

press windows+R open RUN Window

services.msc 

find SQL Server(SQLEXPRESS) right click on that and start the service then check

Answer 5

I got a similar problem with sql server , I have tried every thing but does not connect to database engine & it shows error:26.

• First check if the database engine is running or not. by going into configuration manager. start > sql server >sql server configuration manager. On the right pane you should see the sql server (mss .. ) should be running state with a green indication.

• IF the database engine is not running, simply uninstall sql server / format your system if possible and then download sql server 2012 and management studio. from
  https://www.microsoft.com/en-ca/download/details.aspx?id=29062

• Install server first, make sure to add server on installation phase
  by clicking add server and then install management studio.