File upload fails without error I try to upload a file larger than the 16 MB Craft limit. The file I try to upload is 61 MB.

I have set the maxUploadFileSize to 256000000.
My hosting company changes the server PhP settings to this:

max_file_uploads = 20
upload_max_filesize = 256M
max_input_time = 180
memory_limit = 256M
post_max_size = 256M


The file starts to upload but when the progress bar is at 50%, it just stops. It keeps "uploading" (wheel keeps spinning in the top right corner) but nothing happens anymore. 

I don't get a front-end error either. But in my browser console it says: ERR_CONNECTION_RESET

Anyone who can help me find a solution?

UPDATE

So, my hosting company made the time-out longer and the error dissapeared. 
But I still can't upload the file as I get this error in the console window now:

POST http://krycer.be/index.php/admin/actions/assets/uploadFile 502 (Proxy Error ( The specified network name is no longer available.  ))


When I diasble my proxy I get this error:

POST http://krycer.be/index.php/admin/actions/assets/uploadFile 500 (( The specified network name is no longer available.  ))


The file upload completes, but the status bar remains visible, allthough full, and the file is not visible in the assets folder.
It would be worth checking craft/storage/runtime/logs/craft.log, it's very likely there's a clue in there.