I'm getting the FAILED (Temporary file could not be copied.) for uploads when using a form. What's a bit tricky is that this only happens after I change the owner of my domain to a new user in my web panel (I'm using DreamHost).
The new owner is needed as there are two of us who need to access the uploaded files, so I created a new owner so that we can both share the FTP info and log in to the uploads folder to access the files. This is what is recommended by DreamHost.
I've gone back and forth with DreamHost and this is not a problem with any server settings - all of the permissions are correct and all the subdirectories list the new domain owner correctly. I have updated my php.ini to accept large files and this is verified in WP > Media > Add New.
I have tried all of the solutions suggested in these forums and nothing works. Again, once I change the owner back to me, the uploads work fine. As client submissions are basically the main feature of our site, I really need to get this working.
Yes, I could give my business partner the original domain owner login/pass but then he has access to all my other domains which I don't want to do.