I get an error There was a problem acquiring a personal certificate required to sign in. If the problem continues, please contact your support team. I'm using Windows 7 and have an office 365 account which is where Lync is hosted.

I've tried all the troubleshooting and no joy, also doubled check if there is a Lync certificate in the personal store, and none located.

See original post http://community.office365.com/en-us/f/166/p/289095/882945.aspx#882945

• Edited by BuddyHome Thursday, January 22, 2015 9:39 AM

HI

Can you delete your Lync certificates on your front end server and your local client.

Clean on your client also your sip-directory and signin again.

you get a new certificate from the server after you delete the old one on FW-Server and Client.

BR

Hi buddyHome,

The following steps should be able to resolve your problem.

1. Delete the sign in information.

Click Delete my sign-in information and Lync 2013 will automatically remove any saved password, certificates, and connection settings for the user account.

2. Delete the Lync User Profile and Registry Key.

User profile:

%userprofile%\AppData\Local\Microsoft\Office\15.0\Lync\sip_UserName@Domain.com

Registry Key:

HKCU\Software\Microsoft\Office\15.0\Lync\UserName@Domain.com

3. Revoke the client certificates on Lync Server

Run the following command in the Lync Management Shell:

Invoke-CsClientCertificate Identity UserName@Domain.com

If the issue still exists, please feel free to let me know.

Best regards,

Eric

• Edited by Eric_YangKModerator Friday, January 23, 2015 6:02 AM

HI!

The easy way to solve this issue is applying the following command from cmd:

certutil -delstore -user my user@domain.com

Using this command, we delete the cached certificate causing the problem.

Best Regards

I've tried item 1 and 2. But don't have access to do so 3. I'm using Office 365 which is hosting the lync server

i typed certutil -delstore -user dhirani@treotech.co.uk and it comes back with missing argument error. Expected at least 2 args, received 1.

The command you ran might not work.
Did your account ever worked? What happens when you try to login to Mobile Device?

Mobile device works, also works on another windows and mac computer

I can see there is no personal certificate for lync installed. It looks like its unable to install the certificate. How do I install it manually?

Hi BuddyHome,

Can you create a new Windows User Profile or log in to another user account to test ?

Best regards,

Eric

Created a new profile and got the same problem. I gave up so re-installed windows and now problem solved.

• Marked as answer by BuddyHome Monday, January 26, 2015 11:09 AM