You should be able to post a thread regardless of your post count, sometimes the spam filter picks up certain words and stops it being posted, hopefuly admin can help you further, but you should be able to start a thread

@admin, ive seen this issue a lot, and i wonder how many people have signed up, cant post due to whatever reason and just bugger off

We could be losing a lot of potential forum members due to the spam filter or whatevers causing it