After this configuration, our user outlook prompt the autodiscover change to "autodiscover.xyz.com" and some user connect to ex2016
In a coexist environment, it is suggested and needed to use Exchange 2016 as client access point(if only publish one Exchange server to the Internet), because Exchange 2016 could proxy request to Exchange 2010, but not vice versa. Client Connectivity in an Exchange 2016 Coexistence Environment with Exchange 2010
The URLs geted by Autodiscover service also decided by where mailbox hosted. So, make sure all "@jaswant .com" mailboxes are hosted on Exchange 2010 database.
Then, use command below to check and backup autodiscover original configuration:
Get-ClientAccessServer | fl Identity,*uri*
Then use command below to remove SCP from all Exchange servers:
Get-ClientAccessServer | Set-ClientAccessServer -AutoDiscoverServiceInternalUri $null
After that, make Exchange 2010/2016 use the same internal URL as their external URL(Exchange 2010 using "abc.com" and Exchange 2016 using "xyz.com").
Then restart IIS service(Run "IISReset" command in CMD) on all Exchange servers. Wait for a while, then check again.
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