Today , i encountered a wiered thing in my SQL Server Management Studio 2008 R2 where the intellisense was somehow not working in SSMS 2008 R2 .
I had only SQL Server 2008 R2 Express installed on my machine and had recently installed the Microsoft Visual Studio 2010 Service Pack 1 on my Windows 7 System and assumed that this could have caused the issue .
If you are one of those users who faced the same issue , there is a fix from Microsoft Support website for this error.
To resolve this issue , you should apply the cumulative update that includes the incompatibility between SQL Server Management Studio 2008 R2 and T-SQL that is part of Visual Studio 2010 SP1.
I downloaded the Build 10.50.1815.0 that was released on April 16 , 2012 and installed it .
You can find the list of The SQL Server 2008 R2 builds that were released after SQL Server 2008 R2 was released here
Read more about the Fix for IntelliSense feature in SQL Server Management Studio 2008 R2 may stop working after you install Visual Studio 2010 SP1 from Microsoft Support Center.