I am the administrator on a brand new guild site. I have set up the ranks and all that fun stuff. However after people register on the site and I grant them access they still can not post on the forums. Not even the person I gave the rank of Guild Master. Any help would be great. Thanks!

Check the thread tag permissions in the Admin > Forum > Thread Tags (Categories). They're likely set too high.

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Followers of Nobility

The problem actually happens to be (in this case) that the accounts themselves weren't being promoted to the proper ranks, only the characters.

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It's all in the reflexes.