I had an issue with Autodiscover for one user, it works perfectly well for others.

  • User machine connected with domain
  • No VPN
  • User logged in with domain account
  • Autodiscover url returns 600 error code

Test auto-configuration failed and not able to download OAB, it returned (0x800C8203) error code which helped me to find the below article.


As the above article says I tried removing msExchDelegateListLinkBL using below command.

Set-ADUser <user> -Clear msExchDelegateListLink

But unfortunately did not help because it was a terminated user in my case, even after waited for so long msExchDelegateListLinkBL value was not gone away.

Then I followed the below steps to fix the issue.

  • Connected the terminated user from disconnected mailbox
  • Granted full mailbox access to faulty user
  • Removed full mailbox access
  • Run Set-ADUser <user> -Clear msExchDelegateListLink
  • Verified msExchDelegateListLinkBL value has been removed properly
  • Disable the mailbox

Autodiscover started working immediately after removing msExchDelegateListLinkBL value.

Thanks a lot to Jim Martin, you saved my day.