On error vba ???

[Alpacino]

I have a macro that only works if the file that it copies from is open
Eg. Code is windows("Alan1.xls").Activate
Undone want to change this line of code.

I want to say On error then msgbox " you must make sure Alan.xls is open to run macro"
Anyone help please.
Thanks

 

[ChrisOswald]

Norie; Thanks for the insight -- it's pretty much what I already thought, I just wasn't completely sure if setting an dummyobject to a test object would eat up memory or something.