The technology running the site has been upgraded. Most services run exactly as before, but the forum has been discontinued.
Forum posts that described the version history of a calculation have been migrated as comments on the relevant calculations.
Forum posts concerning XLC have been migrated as comments on XLC (look at the main menu for the first item under XLC Addins).
Otherwise, consideration is being given to whether there should be some kind of forum or perhaps question and answer service. Please contact us if you have a view on this.