From the Board Rules page:
Initial Restrictions to Protect Existing Members:
Each new member that registers is automatically assigned to the "New_Users" group. In order to protect existing membership from SPAM and those who might register just to sell their stuff, promote their business, post polls or use our search engine for research purposes, or for similar reasons other than participating as a member in this community, we place temporary restrictions on new members. These restrictions are removed when one of the following is satisfied.
(1) reaching 25 approved postings in the community forums, each new user is automatically moved to the main users group and gains full member standing and benefit.
(2) a new_user can also petition the moderators for full user status after they have been a member for 30 days. This is not automatic, you have to ask.
Restrictions placed on new users until one of the above options is satisfied:
(1) no write access to the Classifieds (Buy/Sell) Forum