I upgrade my confluence from 3.5 to 4.2. Everything went smoothly. I can view the contents with no problem after upgrading.
However, when I tried to modify a page, I kept getting the error message "Error saving draft. No draft has been saved." If I use the save function, the contents will be saved just fine.
When I tried to upload an image and user insert image function to insert it into a page, I will not be able to see anything in the page. I checked the log and found the image was uploaded correctly.
When I tried to insert a link, the search function is not working with the error message "There was an error communicating with the server, please try again later."
Anyone knows the possible reason for this? Thanks a lot in advance