Test MS SQL connectivity

A simple and quick way to check SQL connectivity: create a text file on the client computer, change its extension to udl, save and open it. The "Select or enter a server name" dropdown menu lists all visible instances of available servers.

Hidden SQL instances:

All SQL instances are listed under:

HKLM\SOFTWARE\Microsoft\Microsoft SQL Server\

MSSQLxx.instancename

To identify the hidden SQL instances, check the following registry key:

HKLM\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL11.instancename\MSSQLServer\SuperSocketNetLib\HideInstance

1 = Hidden
0 = Not hidden/browsable

Discovery Wizard for SQL Server
Hide an Instance of SQL Server Database Engine
SQLPing
Test remote SQL connectivity EASILY!