Posted by Centerpoint
Henagon

Teamviewer getting blocked

We provide IT service for a large scale company using Teamviewer as a first line of remote support.  Their firewall is blocking our TeamViewer connections and they are requesting a list of IPs or Ports to whitelist.  Can anyone help with this?

7 Replies
1 Accepted Solution

Accepted Solutions
Posted by iainwels
Pentagon
Solution

Re: Teamviewer getting blocked

Hello Centerpoint,

Here are the ports that teamviewer uses,
https://community.teamviewer.com/t5/Knowledge-Base/Which-ports-are-used-by-TeamViewer/ta-p/4139/jump...

And i just recommend to whitelist *@teamviewer.com

I don't think they blocked all overseas IP adresses

I hope this helps!

With kind regards, Met vriendelijke groet,
Iain Wels,
ICT-Support
If you found this helpfull please verify it as an solution, so it could help other people
7 Replies
Posted by iainwels
Pentagon

Re: Teamviewer getting blocked

Hello Centerpoint,

Maybe it is a bit obvious and i think you know what i am saying but did you try adding a rule (for teamviewer) to the firewall? What kind of virusdetection do they use?

With kind regards, Met vriendelijke groet,
Iain Wels,
ICT-Support
If you found this helpfull please verify it as an solution, so it could help other people
Posted by Centerpoint
Henagon

Re: Teamviewer getting blocked

They run Sophos enterprise antivirus and Barracuda firewall.  They claim to have rules for Teamviewer in place (it used to work fine up to 30 days ago) and now they want to whitelist the IPs where the connections are coming from.

Posted by iainwels
Pentagon

Re: Teamviewer getting blocked

Hello Centerpoint,

Why do they want to whitelist the IP's where the connections are coming from? Is it becouse they think everyone could get on their pc's by using teamviewer (than you can say that you could put a password on the connection). But i will look something up for you how to whitelist an ip in teamviewer.

With kind regards, Met vriendelijke groet,
Iain Wels,
ICT-Support
If you found this helpfull please verify it as an solution, so it could help other people
Posted by Centerpoint
Henagon

Re: Teamviewer getting blocked

I think they specifically block overseas IPs due to hacking, spam, etc.  They have very large customers so their firewall has to be locked down.  We are located in the US so I'm going to assume most of TeamViewers incoming IPs are European based.


 

Posted by Centerpoint
Henagon

Re: Teamviewer getting blocked

The business we service has over 200 computers on their network.  Teamviewer will literally not make it through their firewall to any computer.

Posted by iainwels
Pentagon
Solution

Re: Teamviewer getting blocked

Hello Centerpoint,

Here are the ports that teamviewer uses,
https://community.teamviewer.com/t5/Knowledge-Base/Which-ports-are-used-by-TeamViewer/ta-p/4139/jump...

And i just recommend to whitelist *@teamviewer.com

I don't think they blocked all overseas IP adresses

I hope this helps!

With kind regards, Met vriendelijke groet,
Iain Wels,
ICT-Support
If you found this helpfull please verify it as an solution, so it could help other people
Posted by ErickOwens917
Photon

Re: Teamviewer getting blocked

We ran into this issue today.  At my network we block all traffic not originating from within the US.  Our helpdesk was able to connect the day before.  Ran a trace route found the *.teamviewer.com site was running through Microsoft Azure.  That being the case we started adding country code one by one based off of Azure Data Center locations.  When we got to Hong Kong teamviewer started working again.  Bottom line was we had to trace out what country the teamviewer traffic was routing, allow said country, and got resolution.  Obviously for businesses that block by country codes this is not an ideal solution and poses a security risk.