It's been buggy for years. Read http://forums.adobe.com/thread/736644
The same workaround I use is not to use DLM.
Bob
Tried to download Adobe Reader X but keep getting message saying "Windows has blocked this download because can't verify the publisher". My OS is Windows XP(Service Pack 3) and I use IE 8 for my browser. I also tried with Firefox but I get the same message. I even disabled Windows Security Essentials, my only AV software installed.

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