I have put TFU to work within a prepress asset management website for our customers to upload files. It has been working well for the most part although I still have a couple of bugs to work out but they haven't seemed to cause any problems. We usually use https and haven't seemed to have any problems with that either.
Anyway, one client tried to upload last night and this morning and got the error:
Status: Retry failed. Please check your timeouts
as soon as he clicked the upload button. I couldn't find any errors in the apache log files or in the tfu log. I think he tried both http and https, but don't hold me to that. I can't replicate it here and other customers have uploaded successfully today.
This is standalone TFU embedded in a web page with a form. The version is 2.10 (although I see the 2.11 is out now).
Any guesses? I will be on vacation for a few days so I may not be able to get right back to you but I wanted to start this while it was fresh in my mind. If you want, I can set up a login for you.