John,
It is, as ever, never that simple. There were a whole raft of changes implemented to try to stop the spam attacks earlier this year. Most were not visible to users. However, the combination of two different actions inadvertently stopped non-logged in users seeing the forum. This went undetected by everyone for some time as all the regulars are logged in. It was only when, some time later, Google removed all the indexing, that this issue was discovered and highlighted on the forum. That was on the Saturday. Duncan, who is now our IT guru, investigated and it took two separate actions