Forum posting is one of the privileges of Premium membership.
If you are a Basic member, or have signed up for a Premium Membership and we have not yet received your payment for the membership, you will receive the error "Only paying members can post to forums".
An unfortunate side effect of this is that during the period where There is down for maintenance each morning, those checks fail because There's servers cannot be queried. This means that some paying members may be turned away with the above error, because the forums cannot actually verify the Premium membership status. We apologize for any confusion or inconvenience this may cause.
One of our members has posted a workaround that seems to function. If you open up
http://forums.prod.there.com in an outside browser (like Internet Explorer) at least five minutes before the maintenance window, forums will then function normally throughout the maintenance period. We have not tried this ourselves, but we have heard good things about it.