Hi, all I want to do is use wpForo behind a single Welcome page on the simplest community site you have ever seen. I had tried another plug in, but it seemed to break my Twenty Eleven theme and I was forever calling for backups. I have deleted that plug in now, and the 3 pages it created. Now I can't get anything to work. The wpForo is activated but none of my pages load correctly, they (there is only Welcome and Forum) appear briefly but then vanish and are replaced by the website name in the top left hand corner of the page. The theme seems to have been broken as well. Can anyone help me please?
Some plugins leave traces behind and that is why it is a good idea to take a backup before installing or upgrading plugins. If you have a backup, see if you can restore that.
You can also delete that theme and see if it fixes the problem.