> Thanks for the suggestion, but I don't think that will work, for two
> reasons:
>
> They could be running it on a client machine, pointed at a shared
> destination on a folder. The MUTEX would catch that.
>
> If an earlier installation died part way through, I want to know that
> it was underway and unfinished, so that the support staff can ensure
> that it's OK.
>
> That's why I was leaning toward using creating a file called
> "Installing!" in the destination folder. If the file existed, then
> they could not proceed with a subsequent installation. That file
> would be deleted near the end of the install script (after everything
> has safely completed).

Okay, understood. Then just create a, say, text file when you start the
installation process ("Handle Text File Operation -> Create File"). Then
you can use "If File/Folder..." to see if the file exists and to determine
an installation is underway. At the end of the installation, use "Delete
File(s)..." to remove your file.

Do you think this could work?

Friedrich