Mail contacts in exchange are not showing in distribution lists on the client side

contactsdistribution-listsexchangeexchange-2013

I have an exchange 2013 server.
We have mail contacts set up for some external contacts.

There are several distribution lists which contain these mail contacts.

When an internal user inspects the distribution list through outlook, the mail contacts are not shown.

When I open exchange shell and run

Get-DistributionGroupMember "MyGroupName"

I get the full list of users including the mail contacts.

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I have checked the contacts and none of them are set to 'hide from address lists'.

Does anyone know how to include these recipients in the list as far as outlook is concerned?

The following is an output of get-mailcontact…

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Best Answer

So just on a fluke, I managed to solve this issue... Thanks to LeMoore, as his comment sent me down the right path. Once I realised I couldn't see the mail contacts in the GAL that got me thinking...

This is a multi-tenant mail server and isolation is achieved using filters and customattribute1.

When the mailcontacts were created, as there is no option for customattribute1, It appears that my colleagues never set it.

I applied the correct value to customattribute1 via the shell and hey presto, suddenly the users can see the mailcontacts in the GAL and they appear in the distribution lists.

Thanks for the assistance guys!