File transfer in OpenFire 4.4.4

Openfire
1

I have updated OpenFire from 4.3.2 to latest 4.4.4. I have used executable file downloaded and update goes smooth. BUT after update file transfer function goes to malfunction. File transfer from inner clients to outer clients goes and from outer clients to inner clients does not go. Inner clients are clients inside LAN behind the firewall who connects to server directly. Outer clients are WAN clients connected through internet.
Before update file transfer did work as expected.
And now i see in Error log on server these lines:

> 2019.12.17 01:50:36 org.jivesoftware.openfire.filetransfer.proxy.ProxyConnectionManager - Error processing file transfer proxy connection 
> java.io.IOException: Only SOCKS5 supported 
> at org.jivesoftware.openfire.filetransfer.proxy.ProxyConnectionManager.processConnection(ProxyConnectionManager.java:156) ~[xmppserver-4.4.4.jar:4.4.4] 
> at org.jivesoftware.openfire.filetransfer.proxy.ProxyConnectionManager.access$200(ProxyConnectionManager.java:53) ~[xmppserver-4.4.4.jar:4.4.4] 
> at org.jivesoftware.openfire.filetransfer.proxy.ProxyConnectionManager$1$1.run(ProxyConnectionManager.java:125) [xmppserver-4.4.4.jar:4.4.4] 
> at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_202] 
> at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_202] 
> at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) [?:1.8.0_202] 
> at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) [?:1.8.0_202] 
> at java.lang.Thread.run(Unknown Source) [?:1.8.0_202]

What does it means? Can it be fixed?
During update i did update plugins. I’ve got a few of them. Bookmarks, Certificate manager, HTTP File Upload, Jingle Nodes, Monitoring service, Search.
I’m thinking about restoring previous version (4.3.2). I’ve got full directory backup as well as DB-backup. Is it better way or should I wait?

2

Hmm, I’m not aware of any related changes between 4.3.2 and 4.4.4.

Openfire supports many types of file transfer. Can you tell me which variant your clients are trying to use? What clients are you using?

3

We are using PSI+ clients on both sides. And we use builtin service “socks5 proxy” of OpenFire server. It works through 7777 port. In services discover window in PSI+ client I can see it as “SOCKS5 Bytestreams service” with JID “proxy.FQDN” and options supported “http://jabber.org/protocol/bytestreams” and “http://jabber.org/protocol/disco#info”.
An alternative way to transfer files is “in-band”. I have tested this option (on previous version) and it is too slow.
The most valuable information about file transfer i’ve found in this forum post: https://igniterealtime.jiveon.com/message/183112#comment-183112. After i have implemented settings mentioned in post above on OpenFire version 4.3.2 all clients have been able to transfer any files.
Now i have checked the settings on version 4.4.4. All the settings are the same but file transfer works one way only.