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Exchange 2010 - 2016 migration user mailbox migration issue

Brass Contributor

we're migrating from EX2010 to EX2016 and testing the user migration process.

The exchange 2010 CAS Array is configured as cas.domain.local ( that was configured by others ) and we see outlook using that fqdn to connect to.

Autodiscover URL has been set for all  the exchange server to point to new exchange server

URL on the EX2016 has been set to OWA.domain.com

 

we tested the migration of one user mailbox but when it starts outlook we see it fails to connect to exchange server ( the new one ) since is still trying to access "cas.domain.local" and the user is prompted for credentials which, then, are not accepted.

If we set cas.domain.local in the hosts file pointing to new server  it connects to exchange 2016 without issues.

 

Shouldn't the outlook client reconfigure itself  by looking at autodiscover ?

thanks

 

 

9 Replies
Thanks
I know I have to enable Outlook Anywhere on 2010 I was wondering if that would have any impact on the users
Hello Dan,
If I got it right, and remeered correctly from previous migrations, all the EX2010 services URL should be directed to Exchange 2016, is that correct?
Both Internal and External URL.
Yep...client connectivity and mail flow gets migrated to Ex2016 first, then migrate your mailboxes
@Dan_Snape
I've enabled OutlookAnywhere on exchange 2010 with external URL pointing to the Exchange 2016 server
I've also set the OWA,ECP,ActiveSync URLs of exchange 2010 to point to exchange 2016.

The only thing I did not change so far is the FQDN of the CAS Array in exchange 2010 which still points to Exchange 2010.
The problem is that with this configuration.
- Mailbox migrated to exchange 2016 are not able to connect.
- Mailbox still on Exchange 2010 still connects.
If I set the CAS FQDN to point to exchange 2016
- Mailbox Migrated to EX2016 are able to connect
- Mailbox still on EX2010 do not connect
Does the AutoDiscoverServiceInternalUri for all servers use a name that points to the Exchange 2016 server (get-clientaccessservice | select AutoDiscoverServiceInternalUri)

client access array isn't used by Exchange 2016
Yes all the server have the autodiscover configured to point to exchange 2016
Name AutoDiscoverServiceInternalUri
---- ------------------------------
EX2010-01 https://autodiscover.company.com/autodiscover/autodiscover.xml
EX2010-02 https://autodiscover.company.com/autodiscover/autodiscover.xml
EX2016-01 https://autodiscover.company.com/autodiscover/autodiscover.xml
EX2016-02 https://autodiscover.company.com/autodiscover/autodiscover.xml

Name: autodiscover.company.com
Addresses: 192.168.102.18
192.168.102.17
the IP are the IP of EX2016 servers
@dan
I know that Exchange 2016 shouldn't use CAS but the problem is there's must be something with autodiscover not working properly because is a fact that the outlook client for the migrated mailbox is using cas.company.local to access the mailbox since if I set it on the hosts file it connects.

Looking at the Exchange 2016 Mailbox Database I see that the RpcClientAccessServeris set to the CAS FQDN
Name RpcClientAccessServer
---- ---------------------
MBX2016 cas.company.local
best response confirmed by Stefano Colombo (Brass Contributor)
Solution
Yes all the autodiscover point to the exchange 2016 server.

I found what the issue was.
On the client there was a registry key MapiHttpDisabled set to 1 .
I changed it to 0 and the client connected fine
thanks
1 best response

Accepted Solutions
best response confirmed by Stefano Colombo (Brass Contributor)
Solution
Yes all the autodiscover point to the exchange 2016 server.

I found what the issue was.
On the client there was a registry key MapiHttpDisabled set to 1 .
I changed it to 0 and the client connected fine
thanks

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