SQL Server 2008 setup error Attempted to perform an unauthorized operation

I am trying to install SQL Server 2008 Standard Edition on windows 7 and during installation it give error:

Attempted to perform an unauthorized operation

From serverfault $pageUsers[$entry.posts[0].author].name

• check your disk privileges - assume you are admin on the machine.

  From $pageUsers[$post.author].name

• yes you are right it is problem of priviliges when i give premission as a amdinistrator in registry it installed without any problem.

  From muzammil