Well, it means a couple of things could have happened...

• The archive is invalid because it was downloaded incorrectly. (Eg. you did not download the whole archive, try again.)
• Sometimes, tar.gz files are not opened correctly with winzip. Try downloading and installing cygwin and then do a tar -zxvf on the file and see if you can install it. (Also, cygwin itself has a copy of perl available, which you can select for download under the 'interpeter' section of the setup window...)
• Are you using Activestate perl? Why not use the native ppm interface? (Do a perldoc ppm from the command line or you can browse the documentation.)

Good luck. :)
Zak

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Zak