Using the Standard "Open File" dialog box

The following is an example of how do use the "Open File" dialog box according to the VBA help files:

fileToOpen = Application _
.GetOpenFilename("Text Files (*.txt), *.txt")
If fileToOpen <> False Then
MsgBox "Open " & fileToOpen
End If

My code looks exactly like this (aside from the MsgBox) but when a user chooses a file to Open, I get a "Type Mismatch" error for the If condition since fileToOpen contains a path now, and not a boolean. I have this feeling I'm missing something obvious but I'm not sure what it is.

Thanks,

Geoff