I tried this...

but unfortunately , i get a error..

Error: Failed to lock variable "User::WqlquerySource" for read access with error 0xC0010001

"The variable cannot be found.

This occurs when an attempt is made to retrieve a variable from the Variables collection on a container during execution of the package,

and the variable is not there. The variable name may have changed or the variable is not being created.".

when i validate this expression it works fine, but it gives error when i hit the execute button...

Guys, Could you help me , where am i doing the mistake?