You may have noticed that you can't see the private forums for X-group that you are a part of.
Proceed directly to your User CP and look in the sidebar on the left. Towards the bottom there is something called "Group Memberships"
Click this. You will see a listing of available user groups. Your private forum access is tied up with the corresponding user group. Click on the one you want to join and one of the moderators for that group will approve you.
Voila! Your access is back.
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