I would like to prompt a user to activate a workbook and then use that
workbook as a variable later on.

The code I have come up with is

MsgBox "Is the printer on?", , "Caution"
Set book1 = ActiveWorkbook

When I run the procedure it does not give me an opportunity to activate
the workbook open in the background. I want to be able to click on a
workbook and then click OK. In other words, how can I make a MsgBox
display vbmodless?

Please help. Thanks in advance.