I successfully used a site requiring J/Js to run many times over some months, then suddenly I could not access it. I eventually got J and Js fully re-enabled but remained puzzled about why they were suddenly disabled. I found out a couple of tips - might help others with similar probs. 1. (Accidentally) restoring default user profile restores default IE settings (including J etc). 2. Downloading and running some s/ware (eg some ad killers) alters J etc settings.