Microsoft Exchange groups (lists) contained in other groups are ignored

I have several groups (distribution lists) defined under Contacts in a Microsoft Exchange account. Some of the groups contain other groups. On sending an email to such groups, the other groups contained within, are ignored.

For example:

group1 =,
group2 = group1,,

When sending email to group2, I expect the email to go out to,,, But the contained group1 is ignored, and the email goes out to only,

NOTE that these groups were defined outside of eM client (from Outlook), and work fine in the Outlook client.

It could be a limitation of the way eM Client accesses the Exchange data. In eM Client when you include one distribution list inside another, it unpacks the addresses so you have just a single combined list of names and addresses.

If you have a Pro License, you could open a support ticket and eM Client will be able to help you further.