Outlook 2010 Prompting for Certificate

Getting error in my lab (domain shown below is just for reference purpose only)



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Outlook 2010 Prompts for Credentials after rebooting ... Incomplete

Troubleshooting Steps
1. Check Connectivity with Exchange server
. Host file entry for CAS server on client machine to bypass when there is Load balance is involved
. Certificate expiration
2. Is Outlook Prompt when it is connected from Internet or Internally
 .  When it is prompting for Password
 . Is OWA is behaving the same way
2. Check which Process is Prompting for Password
   (a) Certificate
   (b) OAB download
   (c) Autodiscover
   (d) Has AD users changed Password

. Create a new Profile if they had been Migrated from the legacy Exchange version
. Run from the Shell "Test-Outlookwebservices -Id:Alias | FL" and check if Autodiscover has an Issue
.Outlook Connection tab and uncheck "Fast connection"
. Check msstd:"have a correct certificate name"
. Reset Autodiscover from Exchange management Shell