Skype for Business Problem Acquiring a Personal Certificate

Hi Ashwini,

Thank you for contacting us. If you have tried to clear Skype for Business cache files and manual configuration in that thread, please follow the steps below to check if it helps.

1. Open Windows Certificate Manager. To do this, press Windows + R, type certmgr.msc, and then click OK.

2. Expand Personal, and then expand Certificates.

3. Sort by the Issued By column, and then look for a certificate that's issued by Communications Server.

4. Verify that the certificate is present and that it isn't expired.

5. Delete the certificate and try to sign in to Skype for Business Online.

While if the issue persists, please try to delete your Office 365 account credential in Credential Manager.

1. Open Control Panel, and then click Credential Manager.

2. Locate the set of credentials that's used to connect to Skype for Business Online. If you cannot identify them, you can backup all the credentials and then remove them all.

3. Expand the set of credentials, and then select Remove from Vault.

4. Try to sign in to Skype for Business Online again, and then type your new set of credentials.

Regards,

Marvin

Thanks Marvin,

I had tried the first suggestion before and after reading your post without success. In fact, I don't see any certificate issued by a "Communication Server". I have only two certificates in the folder in which one issued by MS-Organization-Access and the other issued by Apple.

I also tried using the second suggestion. However, Credential Manager  shows four credentials for MicrosoftOffice16Data that is related to the Skype. Deleting those either from the Skype App or directly within the Credential Manager does not help. I see 8 such entries in the Credential Manager of my home PC.

This issue occurs only on my work PC and limited to the Skype for Business Desktop App. I am able to successfully login into the App on my home PC using exact same credentials and within a browser on my work PC.

Therefore, there are two differences between my work and home PCs. One, home PC has the certificate issued by "Communication Server" and generates 8 credential entries for the MicrosoftOffice16Data when successfully logged in.

Regards,

Ashwini

Hi Ashwini,

Based on my knowledge, the certificate issued by Communication Server should be downloaded behind scene when you try to sign in Skype for Business. But for somehow, it failed to download the certificate so that Skype for Business server side cannot verify your account. 

In this scenario, you can try the following steps to check if it helps.

1. Sign in Skype for Business in your home PC. This step is to refresh the certificate Expiration Date.

2. Open Certificate Manager and find the certificate issued by Communication Server.

3. Right click the certificate and select All Tasks > Export > Next > ... >Next to export it.

4. Copy the certificate to your work computer and import it to the same location. 

While if the issue still exists, I'd like to collect Skype for Business log file to do the further analysis. Please follow the steps below to collect it and then send to us in Private Message.

1. Open Skype for Business and delete the sign-in info, then completely exit.

2. Navigate to the following path in File Explorer: %userprofile%\appdata\local\Microsoft\Office\16.0\Lync.

3. Delete the sip folder and all files in Tracing folder (do not delete this folder).

4. Then open Skype for Business and reproduce this issue.

5. Compress the Tracing folder and sent it to us. 

Regards,

Marvin

Hi Marvin,

Thanks for your reply and suggestions. I tried those steps unsuccessfully. After deleting login credentials, the imported certificate also gets deleted. I am sending you the log and compressed Tracing folder in the private message.

Regards,

Ashwini

Hi Ashwini,

Sorry for the late reply since I was out of office. I've received the log file, and it may take several working days to analyze it. I'll post back if there's any progress.

In the meantime, you can try to create a new Windows profileand check if the issue caused by the corrupted profile. Besides, it's also available to perform a clean boot in Windows to start Windows with a minimal set of drivers and startup programs and check if it helps.

Regards,

Marvin

Hi Ashwini,

I've checked the log file and it failed to download the certificate from the server to your computer. Here is the part of the log.

The reason why it failed to download the certificate could be one of the certificates in the chain is untrusted so that it can’t be validated. To further confirm if it's related with the configuration of this computer, please check if your colleagues can sign in their accounts in your computer. Meanwhile, may I know if you have tried the suggestions mentioned in my last reply? If so, please let me know the result.

Besides, it seems the log you collected is incomplete (usually it includes .UCCAPI and .ETL files), please make sure it's Full log. If not, please try to re-collect it and send us in PM.

As a workaround, you can also try to use Teams app since currently Microsoft is planning to upgrade Skype for Business to Teams. And most features of Skype for Business are now available in Teams. 

Regards,

Marvin

Hi Ashwini,