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Recently I have received several e-mails asking for help and advice for building OCS applications. While I normally do try to take the time to answer these to the best of my ability, with coding speeding up and more deadlines to make it seems unlikely that I will have a lot of spare time in the next several weeks.
Probably the best place to post these questions anyways is at http://forums.microsoft.com/ocs2007/default.aspx?siteid=57. This site is monitored by members of the OCS team here at Microsoft as well as by OCS MVPs. Therefore, you have a very high chance of finding the answer to your problem there.