My SQL Server Instance is not visible from another Machine

This has happened because somebody has changed the settings for the SQL Server Instance.To rectify this issue,Login into the Server Hosting the instance.In my case the instance name is 'Instance1'.

Open SQL Server Configuration Manager



Right Click on the instance name which is not visible while connecting.



Select ‘Properties’->Check if the option ‘Hide Instance’ is enabled.If yes then change it to ‘No’.



You will receive a confirmation and instruction that this change will take effect once you restart the MSSQL Service.



Restart MSSQL service.