Skype is not working with allow rule

[MohamedSharief]

Hi,

We have a demand to allow skype for internal employees. However, we've created a security rule to allow the following applications:

-skype

-skype-probe

-ssl/web-browsing

Still skype couldn't connect with an error message "please check your internet connection and try again".

So I've added *.skype.com/* in the URL filteration > still doesn't work

Also I tried to user web-browsing instead of ssl > still doesn't work

and finally I've added both ssl & web-browsing > still doesn't work

When I checked the traffic log I found the following:

Session end reason: tcp-rst-from-client & tcp-fin & n/a

Does anyone know exactly whats going on here?

[MohamedSharief · Accepted solution]

Thanks for the help guys. I did the allow all rule with one source and when Skype didnt work we realised its not FW issue. However, we pluged the machine directly with the router towards the internet and it didn't work also, then we change the DNS to public on (8.8.8.8) and everything was working perfectly. They have an issue with their DNS server.

[rkoenig]

Nice job, we were experiencing the same issue.  What made you decided to try external DNS servers?  Is there a specific URL that is not being resolved? 

[MohamedSharief]

I believe that might be the reason but honestly I didn't try changing the DNS server on the testing machine till I ran out of all options on PA.

Regards,

Sharief

[SajidAliSajid]

Facing same problem.

Skype in my Organization with these Destination and apps (need simple solution).

skype
skype-probe
office365-consumer-access
ssl
stun
web-browsing
websocket
ms-lync-base
ms-lync-audio
ms-lync-video
rtcp
rtp-base

unknown-udp

91.190.216.0/21
65.52.0.0/14
64.4.0.0/18
52.234.0.0/11
40.0.0.0/8
213.199.0.0/16
157.56.0.0/14
13.107.0.0/16
111.221.0.0/17
104.40.0.0/13

Skype website:

To work correctly, Skype requires unrestricted outgoing TCP access to:

• All destination ports above 1024 (recommended)

  or

• Ports 80 and 443 

support.skype.com/en/faq/FA148/which-ports-need-to-be-open-to-use-skype-for-windows-desktop

Regards,

Sajid