Unable to create protection group in SQL 2005

I am using SQL 2005 and I want to create a group of security. I have followed the required procedure for protection all very properly, and then to I am receiving an error indicating the following:
“This item cannot be protected as a result of some requirement computer code is missing. Make sure that all requirement computer code is put in so defend this item (ID: 31008). Click facilitates looking over the list of requirement computer codes for the chosen item.” The indented SQL Server Volume is operating accurately.
Nevertheless this message was displayed when I attempted to protect a bit of private data.
Can the error be fixed?

