The decision to change the name of the DDE name (for both Acrobat and Reader X) was made for a variety of reasons, not the least of which was due to the new Protected Mode (Sandbox) security model that was introduced. We knew that the change would impact users with existing DDE-based workflows, but the security and functionality improvements that it offers were considered more important to the wider user base. The information about the change was provided to developers as part of our pre-release program and also on various blogs following the release. So the change is permanent, we will NOT be going back to the old model. In fact, we will be changing the 10 (to 11, 12, etc.) as the product continues to evolve over time based on the major version of the product. You should use the registry to find out who owns the .pdf extension to determine what message to send. Leonard Rosenthol PDF Architect Adobe Systems
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