>Hi,
>I used a class in my applications by calling the class "Set Classlib To TestLIB Additive" the class will be resident in my application until i remove the class by using "Release Classlib TestLIB" for cretin reason or condition and reload the class. if the class exits the system give me an error. so what i want is to check if the class is exists before calling it again.

This is taken from one of my programs:

If Not "MINDSEYEREPORTPREVIEWFORM" $ Upper(Set('classlib'))
  Set Classlib To prog\mindeye\libs\MindsEyeReportPreviewForms Additive 
Endif