Cisco Unified CM Administration - Voicemail disconnecting

[BVSC]

Hi All,

We have an issue with our Unified CM, where the voicemail is disconnecting the call , after it asks for the users extension. This is for users on Exchange 2016.

Exchange 2010 UM - Uses voicemail number 499.

Exchange 2016 UM - Uses voicemail number 473.

Unified CM 10.5.2

Calls go through to users voicemail, and voicemail retrieval is fine. Users also get emails with the voicemail without issue.

When an Exchange 2016 user dials the voicemail number from their handset (473), it asks for the users extension, and when the extension is entered, the call drops.

This issue is only happening for users on Exchange 2016. Voicemail is working without issue on Exchange 2010.

Can anyone provide some guidance as to what the issue may be?

[Anurag Srivastava1]

Hello

Do they have any CCS-partition for exchange 2016 users?

it could be a one of the reason when mailbox is having CSS that does not have the partition of the number

Else you need to collect the logs and see what could be the reason.

Thanks

Please rate if it is helpful and mark as accepted solution if applicable...

[Jakke2440]

Hello,

Be aware that Exchange 2016 will run out of mainstream support in October 2020.

and exchange 2019 will no longer support EUM.

I would start to think about using Unity and let Unity deliver the message via EWS in the mailbox.

But back to your problem; EUM on exchange 2010 and 2016 is working different did you follow the adapted instructions and modified the SIP trunk and created the needed dns routing rules?

As an example:(I guess 2016 will be similar)

https://blogs.technet.microsoft.com/canitpro/2014/04/29/step-by-step-integration-between-exchange-2013-um-and-cisco-unified-communication-manager/