Keep your system up to date with the most recent cumulative update package for SQL Server 2008 R2 RTM. This package contains all of the SQL Server 2008 R2 hotfixes that have been released since the initial release of SQL Server 2008 R2 RTM.
CU#2 KB Article: http://support.microsoft.com/kb/2072493/en-us
Understanding Incremental Servicing Model for SQL Server
Previous CU KB Articles:
CU#1 KB Article: http://support.microsoft.com/kb/981355/en-us
SQL Server Sustained Engineering