I've always been on a BES. Using BES, messages, calendar entries, notes, contacts, and tasks are sync'd OTA. If I plug my blackberry into the usb port and run desktop manager, the sync options are grayed out. I can not sync via desktop manager and BES at the same time. But your situation is different in that you are wanting to sync to a different computer not on BES. I am not sure whether you can or not. That's why I didn't reply sooner. I was hoping someone who could specifically address your situation would reply.
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