OC Desktop sync client fails to connect

Desktop
1

Please help us by providing the following info. Before posting please make sure that you're running the latest available version for your oC release: https://owncloud.org/changelog/ + https://owncloud.org/changelog/desktop/

Steps to reproduce
1.connect to restricted use network
2.web prompt asks for user login credentials for web use
3.enter credentials (able to browse web, including remote owncloud instance)

Expected behaviour
client should sync

Actual behaviour
client fails to sync

Client configuration
Client version:2.2.3 build 6307
Client operating system:Win 7 pro SP1 64 bit

Server configuration
Operating system:Ubuntu 14.04.5 (GNU/Linux 3.13.0-96-generic 1686)
Web server:Apache/2.4.7 (Ubuntu)
Database:mysql Ver 14.14 Distrib 5.5.52, for debian-linux-gnu (i686) using readline 6.3
PHP version:PHP 5.5.9-1ubuntu4.19
ownCloud version (see ownCloud admin page):ownCloud 9.1.1 (stable)
Updated from an older ownCloud or fresh install:Updated from older version
ownCloud log (data/owncloud.log):

Pasted image1505x641 38.9 KB

Special configurations (external storage, external authentication, reverse proxy, server-side-encryption):none

2

Looks like you can't get a connection. Does it work on a non-restricted connection?
Perhaps you need to use a proxy (did you try to use the system proxy)? The web-interface is working via this restricted network? Has it been working on previous versions of owncloud? You are using the standard ports (443 for ssl)?

3

Does work on non-restricted network.

Not familiar with setting up proxy, guidance?

Yes, web interface works. There is a prompt to log in which appears for web browser use. Perhaps this is what is blocking file sync. I get similar pop up for team viewer to access web.

I am new to this restricted network.

Non-standard ports.

4

Yes, the sync client most likely can't handle such additional restrictions (how should that be done). You need to remove that prompt for the login so the sync client is able to connect successfully.

Edit

That "prompt" is most likely a basic auth? If yes this won't work:

If its not basic auth its even more unlikely as the client can't do any authentication at a web formula or similar.