Enable CLR in SQL 2008

I added an assembly and created clr functions on my SQL server only to receive the following error when I tried to excute them.

Msg 6263, Level 16, State 1, Line 1
Execution of user code in the .NET Framework is disabled. Enable "clr enabled" configuration option.

To enable clr functions to execute, run the following script:

sp_configure 'show advanced options', 1;
GO
RECONFIGURE;
GO
sp_configure 'clr enabled', 1;
GO
RECONFIGURE;
GO