How about making yourself a little utility prg? I wrote this off the top of my head and didn't test it, but it should give you the general idea.

Use it like this...

IF !SETCLASS("yourclasslibrary")
RETURN .F.
ENDIF
*Proceed to instantiate an object from yourclasslibrary.


SETCLASS.prg
lParameters tcClassLib
tcClassLib = upper(alltrim(m.tcClassLib))
IF !".VCX"$m.tcClassLib
tcClassLib = m.tcClassLib + ".VCX"
ENDIF
IF "\" + m.tcClassLib $ set("CLASSLIB")
RETURN .T.
ENDIF
LOCAL lcOnError
lcOnError = ON("ERROR")
LOCAL llError
ON ERROR llError = .T.
SET CLASSLIB TO (m.tcClassLib) additive
ON ERROR &lcOnError.
IF m.llError
RETURN .F.
ENDIF
RETURN .T.

>Hi All,
>
> I'm using VFP6.0 and issuing SET CLASSLIB TO blahblah ADDITIVE. Is there a way of checking if the class library is already open?
>
>Thanks,
>Gavin...