Lync Online error "There was a problem acquiring a personal certificate required to sign in" - for Office 365

I was attempting to sign into Microsoft Lync Online the other day (part of an Office 365 implementation) and I received this error message...

"Cannot sign in to Lync. There was a problem acquiring a personal certificate required to sign in".

Of course I tried all of the typical stuff - restarting Lync, rebooting the laptop but it didn't help. No other users were reporting this issue - they could all sign in just fine - so I'm assuming it's something local to my Windows 7 64 bit laptop.

I did some research and it looks like something was corrupt with my local cached credentials.  Not sure why - i didn't change my password or anything like that.   I found this article from Microsoft...

http://support.microsoft.com/kb/2604176

Here are the steps from that article that worked for me...

To renew a user account certificate, follow these steps:

1. Renew the certificate in Windows Certificate Manager. To do this, follow these steps:
   1. Open Windows Certificate Manager. To do this, click Start, click Run, 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 is issued by Communications Server.
   4. Verify that the certificate is present and that it is not expired.
   5. Delete the certificate and try to sign in to Lync Online. If you cannot sign in to Lync Online, go to step 2.
2. If you are running Windows 7, remove the user’s stored credentials in Windows Credential Manager. To do this, follow these steps:
   1. Click Start, click Control Panel, and then click Credential Manager.
   2. Locate the set of credentials that is used to connect to Lync Online.
   3. Expand the set of credentials, and then select Remove from Vault.
   4. Try to sign in to Lync Online again, and then type your new set of credentials.