Can't connect to Teams desktop (error caa70004)

Question

Can't connect to Teams desktop (error caa70004)

Mathieu Servant 21

Good day,
I can't connect to Teams desktop (error caa70004, see attached screenshot). Please note that I can successfully connect to Teams online. I tried to use PowerShell to reinstall the packages for ADAL (using command specified here, without success.

Could you please assist ?

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Answer 1

Sharon Zhao-MSFT 25,761 Microsoft External Staff

@Mathieu Servant ,

Does this issue persist all the time? Or what changes do you do before this issue happened?

Does anyone else have the same issue?

According to your description, this issue should be related to the desktop client itself.

Except the suggestions from oscarmh, you could troubleshoot this issue from the following several methods:

Check if the date and time zone are set correctly.
Check if TCP 443 and UDP 3478-3481 ports are opened in your firewall.
Perform a clean boot to exclude the conflict with other applications.
Make sure your Teams client is the latest version.

If the response is helpful, please click "Accept Answer" and upvote it.

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Sharon Zhao-MSFT 25,761 Reputation points Microsoft External Staff

2021-01-13T04:54:18.487+00:00

@Mathieu Servant
I am writing here to confirm if any update about this thread.
If the suggestion helps, please be free to mark it as an answer for helping more people.
Sharon Zhao-MSFT 25,761 Reputation points Microsoft External Staff

2021-01-15T07:39:01.197+00:00

@Mathieu Servant
Haven't received your update for a long time, any update now?
If the above suggestion helps, please be free to mark it as answer for helping more people.
Mathieu Servant 21 Reputation points

2021-01-15T08:44:27.383+00:00
An update :

I do not know how to check if TCP 443 and UDP are opened on windows defender. I did netstat -n in CMD, which gives the output attached.

date and time zone are set correctly

The strange thing is that I can use Teams desktop when I am connected through the internet provided by my university, but I can't at home (on my personal internet network). Apart from my account, there is also an admin account on my computer, but the tec h guys from my university said that it shouldn't matter.

57125-netstats.txt
Sharon Zhao-MSFT 25,761 Reputation points Microsoft External Staff

2021-01-19T10:01:25.297+00:00

@Mathieu Servant ,

According to your description, it seems that your home network has some impact on Microsoft Teams.

About open ports on Windows Firewall, you could refer to this article.

Besides, perform a clean boot to avoid the conflict with other applications.

Note: Microsoft is providing this information as a convenience to you. The sites are not controlled by Microsoft. Microsoft cannot make any representations regarding the quality, safety, or suitability of any software or information found there. Please make sure that you completely understand the risk before retrieving any suggestions from the above link.
Sharon Zhao-MSFT 25,761 Reputation points Microsoft External Staff

2021-01-26T06:03:50.85+00:00

@Mathieu Servant ,
Any updates now?
Mathieu Servant 21 Reputation points

2021-01-28T09:04:29.583+00:00

Opening ports TCP 443 and UDP 3478-3481 ports solved the issue. Thanks!
Sharon Zhao-MSFT 25,761 Reputation points Microsoft External Staff

2021-01-28T09:40:10.057+00:00

@Mathieu Servant ,
I'm glad to hear that.
If the above suggestion helps, please be free to mark it as answer for helping more people.

Answer 2

Oscar Maqueda 611 Microsoft Employee

Hi, internet options.. then

Let me know !!

Mathieu Servant 21 Reputation points

2021-01-07T10:28:24.287+00:00

My internet options are similar to yours, so it's not the problem :
Oscar Maqueda 611 Reputation points Microsoft Employee

2021-01-07T10:31:00.747+00:00

Weird... are you using VPN ¿?
Mathieu Servant 21 Reputation points

2021-01-07T10:34:14.697+00:00

No, I do not.

Answer 3

Oscar Maqueda 611 Microsoft Employee

Try to clear cache of teams, well explained here https://www.uvm.edu/it/kb/article/clearing-teams-cache/

Mathieu Servant 21 Reputation points

2021-01-07T11:12:16.197+00:00

I already tried this, and this does not solve the problem.
Oscar Maqueda 611 Reputation points Microsoft Employee

2021-01-07T17:19:13.703+00:00

OMG... any Anti Virus ? Local Firewall ?

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Can't connect to Teams desktop (error caa70004)

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