Hi
Welcome to Centrify community!
Please try to perform the following steps and see if that would help resolve the issue:
CAC and CACNG tokend must be removed.
The following steps needs to be done on the Centrified Mac as root or sudo:
Open up terminal on the Mac and run the following:
1) #cd /System/Library/Security/tokend/
2) #sudo mkdir tmp
3) #sudo mv CAC* tmp/
4) The Smart card must be removed and re-inserted again.
5) Keychain Access must be opened. The card should appear as "PIV-*".
6) site.mail.xxx web site should be accessible now.
a) (If using Safari browser, the credential association must be removed for site.mail.xxx, so that the right certificate can be selected.)
Please keep us posted with the result and udpate. Thank you!
BR,
Ivan