Skype - Unable to receive group chat messages

I will answer my own question... I hope this will help someone! :)

After struggling a bit, I found some useful commands:

• /dumpmsnp - show details about your connection
• /showplaces - show where you are currently connected

You can execute them in any chat window.

/dumpmsnp command was showing "LoggedOut", but I was online and talking almost normally (except group chats).

System: MSNP: Connection Data:
 * Status: LoggedOut

A lot of people are/were suffering from this problem (here).

To solve this "LoggedOut" issue, try this on any chat window:

/msnp24

and restart your Skype.

After restarting, /dumpmsnp output shows the following status:

System: MSNP: Connection Data (MSNP24):
 * Status: LoggedIn

I don't know exactly why, but the /msnp24 command kinds of converted my account to this protocol and now everything works perfectly.

I've found the solution here.

/msnp24 doesn't works for me, but problem solved.

If you vi ~/.Skype/<your_skype_username>/config.xml, then navigate to the HomeServer tags, you will see something similar to:

<MSNPCore>
  <HomeServer>BAYMSGR2013521.gateway.messenger.live.com</HomeServer>
  <NewThreadAllowed>1</NewThreadAllowed>
  <P2PMigrationAllowed>0</P2PMigrationAllowed>
  <ProtocolToUse>24</ProtocolToUse>

Now test this HomeServer's hostname with traceroute command, e.g. traceroute BAYMSGR2013521.gateway.messenger.live.com above, the last line will got to *** which might because of firewall blocking. So just:

1. Ensure you close any running skype instance(check by ps aux and kill -9 skype_PID).
2. Delete the HomeServer tags in config.xml. Either empty the tags or delete the line should works. Save the file.
3. Start the skype. It should able to send and receive group chat messages now.
4. Check config.xml again, the tags should automatically updated with new hostname.
5. If you test this new hostname with traceroute, it should go to last line which are not ***.