Backticks were supported in Perl 4. But the various Perl 4 ports to DOS-like systems had to use different tricks to get enough memory to be able to run Perl. So I suspect the problem is that asp.exe doesn't like being run from whatever extender your particular port of Perl 4 was built using.

Perhaps you would have better luck with something like:

    system("start asp.exe > asp.txt")
        and  die "'start asp.exe' failed ($?): $!\n";
# or
    system('start '.$ENV{COMSPEC}.' /c "asp.exe > asp.txt"')
        and  die "'start cmd asp.exe' failed ($?): $!\n";
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Since you appear to be ignoring the results returned by qx//, you should be using system instead.

Note that those are just guesses about how to "escape" the theorized problem with the "extender" and other combinations may be required (such as dropping "start" from the second example).

        - tye (but my friends call me "Tye")