"iexplore" does not appear to work on Windows 7.

What else could it be? First, make sure you

use strict;
use warnings;
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as others have said. We know you are not doing that because otherwise $url = would be my $url =. Second, how are you launching your script? Try it from cmd.exe if possible so you can see error messages. Failing that, if you can only launch from Windows Explorer for some reason, then on the last line on your script place:

<STDIN>;
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which will pause the script so you can see perl's console window (commonly, but incorrectly, called a "DOS box"). Hit <RETURN> to exit the script.