And to add to your questions , Geofredo, has the OP actually read the forum in question. It clearly states that it is a read only archive. That'said why there is neither a "New Topic" link nor a "Post via email" link under the Options menu.
You also find, if you look under the "Sub-forums" link, that the forum contains archives for two separate mail lists. There are instructions on how to subscribe to each there.
The one thing that could be improved is that rather than say "You can only post messages by email" it might be better explained as "You can only post via the mail list."
Volunteer Helper - but recommending that users move off the platform!
Once the admin for GregHelp now deleted.