Instance Failure.(system.data) Error in SQL Server 2014

Hi, One day when i started to connect SQL Server 2014 instance using SQL Server Management Studio ,i got an error message “Instance Failure.(system.data) “.So i planned to fix the error by checking the system.

Instance Failure.(system.data) Error in SQL Server  2014 fixed

So first I checked how many SQL Server instances are running in my system .I found two SQL Server instances are installed and running in the system

1.DESKTOP-AEGCR6Q\SQL2008

Microsoft SQL Server 2008 R2 (RTM) – 10.50.1600.1 (X64)

2. DESKTOP-AEGCR6Q\SQL2014

Microsoft SQL Server 2014 – 12.0.2000.8 (X64)

So i checked TCP/IP Port Number of both SQL Server instances .it is 1433 for both SQL Server 2008 and SQL Server 2014 instances.I changed port number of SQL Server 2014 instance to 1434 as shown below

How To Fix Instance Failure.(system.data) Error in SQL Server

Now I started SQL Server 2014 again from SQL Server Configuration Manager in order to effect changes that we made in TCP/IP Port.

Solved Instance Failure.(system.data) Error in SQL Server 2014

Then I tried to connect SQL Server 2014 instance again .It connects and works fine for me.Finally I found How to fix the SQL Server error “Instance Failure.(system.data)” .So both SQL Server Instances were using same TCP/IP port number (1433) .So i changed SQL Server 2014 instances’s port number to 1434 .It worked for me .

Okay friends,this error can be fixed in another way also.i stopped SQL Server 2008 instance and tried to connect SQL Server 2014 instance .it worked for me.

So if you installed more than one SQL Server instances in the system,only one of them can have default TCP/IP port number 1433 at a time.