SQL Server Data Tools package did not load correctly.
Applies to: SQL Server Management Studio 2014, SQL Server 2014 Express, Visual 
Studio 2013.
 
Problem Description.
 
Trying to view the data of a table using Server Explorer or SQL Server 
Management Studio you may get the following error message:
The 'Microsoft SQL Server Data Tools' package did not 
load correctly.
The problem may have been caused by a configuration change or by the 
installation of another extension. You can get more information by examining the 
file 'C:\Users\...\AppData\Roaming\Microsoft\VisualStudio\12.0\ActivityLog.xml'
You may have installed SQL Server Management Studio 2014, SQL Server 2014 
Express, and Visual Studio 2013.
 
Solution.
Try the following solutions:
1. Go to "Programs and Features" in Control Panel, search for "Microsoft SQL 
Server Data Tools", then click on it and select Repair.
2. Apply the latest update for Visual Studio. 
Here you will find Visual Studio 2013 Update 5 for instance.
3. Download the latest version of SQL Server Management Studio from 
here.