Try to identify the message id which is not showing up in outlook:

open the message with sogo-web and check the URL:
https://server.domain/SOGo/so/user/Mail/0/folderShared/folderMail/1030/popupview
-> e.g. msgid=1030

Search EAS Cache for the message id
sogo-tool -v manage-eas listfolders <userid> <deviceid>

If the id is found in SyncCache (e.g. SyncCache = {1030 = 4711 ....}) the message was touched by sogo's eas code but it somehow didn't reach the client.

For some users ActiveSync with Outlook 2013 wont start downloading messages at all, even with new outlook profile. For a while status is "Waiting for a server response" and then changes to "Disconnected from server".

What is in sogo.log when the status changes to "Disconnected from server".
How long does it take until "Waiting for a server response" goes to "Disconnected from server"?

This sogo log when 1 message did not show up in sent folder in outlook. In webmail letter was in sent folder.

192.168.1.254 - - [23/Jan/2015:13:19:04 GMT] "POST /SOGo/so/ott/Mail/0/folderSent/moveMessages HTTP/1.1" 204 0/41 0.336 - - 1M
Jan 23 13:19:04 sogod [14786]: [ERROR] [we-rm] did not find locale for language: Estonian
2015-01-23 13:19:04.902 sogod[10405] -[WEClientCapabilities initWithRequest:]: Unknown WebClient: user-agent='Outlook/15.0 (15.0.4673.1000; C2R; x86)'
Jan 23 13:19:04 sogod [12318]: [ERROR] [we-rm] did not find locale for language: Estonian
192.168.1.254 - - [23/Jan/2015:13:19:05 GMT] "POST /SOGo/so/ott/Mail/0/folderSent/unseenCount HTTP/1.1" 200 13/0 0.247 - - 20K
192.168.1.254 - - [23/Jan/2015:13:19:05 GMT] "POST /SOGo/so/ott/Mail/0/folderSent/headers HTTP/1.1" 200 617/15 0.244 - - 0

Can you try 2.2.15? It contains a fix which changes the sync/ping behavior.
The "Disconnected from server" could be caused by a sync requests which doesn't return immediatly...

2.2.15 version did not solve my problem.

Please be more chatty ...
Do you still get the "Disconnected from server"?
What do you see in sogo.log when this occurs?
You say "form some users..." - what is the difference to users without problems?

I no longer get disconnected from server. I also run version 2.2.16 now. But problem occurs still.

Right now I have a problem with sogo log, so there is very hard to get any information out: http://www.sogo.nu/bugs/view.php?id=3125

Do you still have the issue described on 20.1. (For some users ActiveSync with Outlook 2013 wont start downloading messages at all)?

This was resolved by another technician in our company, who is at vacation right now. I can provide you a solution to that next week.

Customer said that he sees new messages in webmail, but in order to get them to outlook, he must close and reopen outlook manually. Send/recieve wont bring messages to outlook.

So, I assume that the problem mentioned in the initial problem description ( ...select move to->inbox then Outlook downloads these messages...) also doesn't occure any longer.

I would help to have a

tcpdump -i lo -s 0 -w /tmp/dump.pcap tcp and port 20000

when there are message waiting on server but outlook doesn't pick them up.

You can send it directly to me if you don't want to upload.

( ...select move to->inbox then Outlook downloads these messages...) This workaround still makes possible to download non-downloaded messages to outlook.

Potential fix pushed here:

https://github.com/inverse-inc/sogo/commit/cc3652b59b40bcb420d806412277509ac247d85d [^]

Bug suspended for now.