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Audi9112450's avatar
Audi9112450
Brass Contributor
Apr 21, 2023

Exchange 2019 CU12 brand new install ECP redirects to OWA

Hello, Looking for some help from the experts.  I'm a little confused, I have an Exchange 2016 that is acting up so we decided to go towards 2019. Install went fine, Exchange is up and alive servi...
Exchange Server
Andres-Bohren's avatar
Andres-Bohren
Iron Contributor
Apr 21, 2023

Hi Audi9112450 

 

Can you check this

https://learn.microsoft.com/en-us/exchange/architecture/client-access/exchange-admin-center?view=exchserver-2019

  • If your mailbox is located on the Exchange 2010 Mailbox server, you get the Exchange 2010 ECP by default. You can access the EAC by adding the Exchange version to the URL (which is 15 for both Exchange 2013 and Exchange 2016). For example, to access the EAC through the Client Access (frontend) services on the Mailbox server named Mailbox01, use the following URL: https://Mailbox01/ecp/?ExchClientVer=15.

  • If your mailbox is located on an Exchange 2016 Mailbox server, and you want to access the ECP on the Exchange 2010 Client Access server named CAS01, use the following URL: https://CAS01/ecp/?ExchClientVer=14.

Regards

Andres

Audi9112450's avatar
Audi9112450
Brass Contributor
Apr 21, 2023

Andres-Bohren 

 

Hello Anders, 

Thanks for answering.

The old Exchange Databases (the old exchange server) is an Exchange 2016

The new Exchange server is an Exchange 2019

I tried using this URL 

https://mailbox01/ecp/?ExchClientVer=15

It still redirects

I also tried

https://mailbox01/ecp/?ExchClientVer=15

Same error

 

I'm unsure where the redirect is coming from, I'm also very confused as to why everything works properly on the old server

  • Audi9112450's avatar
    Audi9112450
    Brass Contributor
    Apr 21, 2023

    Hello again,
    I did a little digging. I'm unsure if it's related but the old exchange server is having replication errors. It seems like it is unable to accept any changes from any DC.

     

     

     

     

    Last attempt @ 2023-04-21 18:45:42 failed, result 8456 (0x2108):
The source server is currently rejecting replication requests.

     

     

     

     

    I'm thinking the root of the old exchange server being problematic lies there but if I can get into the ECP on the new Exchange server I'm going to try to move the mailboxes over to the new Exchange server and just remove Exchange from the old server and just demote it in about a week. The new Exchange server and the FSMO DC are replicating correctly. 

     

    It would explain why all the new users I am creating cannot log on to Exchange OWA. I checked in AD on the offending server and no new users are present. 

     

    Hopefully someone can shed some light as to why it is getting redirected to the OWA page.

     

    For reference here is the error from the FSMO server telling me that the Exchange server is rejecting requests

     

     

     

     

    ActiveDirectory_DomainService
EventID 1925
Additional Data 
Error value: 
8456 The source server is currently rejecting replication requests.


and from the offending server

ActiveDirectory_DomainService
EventID 2103
The Active Directory Domain Services database has been restored using an unsupported restoration procedure. 
Active Directory Domain Services will be unable to log on users while this condition persists. As a result, the Net Logon service has paused. 
User Action 
See previous event logs for details.

     

     

     

     My registry on the offending server (the Old Exchange) is indeed

    • Path: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\NTDS\Parameters
    • #define DSA_WRITABLE_CORRUPT_UTDV 8

     

    I should add these are Hyper-V servers and I believe the Exchange server VHDX files were copied over from one physical server to another physical server last year. Which is when the errors started showing up. It wasn't done with an export it was just copy pasted and we kept the UUID and didn't generate a new one. I am unsure if that is the root cause of this but I'd like to get the redirect on the new server solved so I can move the mailboxes over.

    Thanks!

     

    PS: One final thing (again unsure if it's related to the redirect) but when I installed Ex2019 CU12 I was forced to download and install IIS URL Rewrite

     

    https://www.iis.net/downloads/microsoft/url-rewrite

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