Also check your cache folder. I had a Cases dashlet that wasn’t working for me for ages. I tried everything. It seemed to be only a “me” problem and could never figure it out. Then I went in to the cache folder found the dashlets. Deleted from the cache folder and then magically that dashlet started working again. I can’t remember exactly where in the cache folder I found it, but you can try that if all else fails.
(Also you can try all the rebuild JS stuff in repair in rebuild)