According to the following link, the following features are not available for Yammer networks in the EU Geo:
- External guests can’t participate in your Yammer Enterprise network.
- Your users can’t participate in other Yammer networks, including external networks.
- Your users can’t be participants in external messaging threads or add external participants to threads in your Yammer Enterprise network.
- External groups can’t be created in your Yammer Enterprise network, and your users can’t participate in external groups belonging to other networks.
Which is a bummer, as from a vendor perspective we have customers from all around the world, and with this limitation –which maybe helps for GDPR- we’ll probably have to look for something else for our external communication? We are losing the strength of external comm with this move. We’ve been getting in touch with a Yammer PM and he confirmed that external networks, access to external networks from new Office 365 tenants created from EU will not be possible.
I had a chat with one of the Yammer PG and here is the official answer:
Thank you for your mail! Sorry for the pain you are facing with external communication with Yammer EU stamp. Moving your Yammer network to the EU does come with the documented limitation that you cannot collaborate with others external to your network. Actually, it has nothing to do with GDPR as Yammer is GDPR compliant anywhere you choose to store your data, be it the US or the EU.
- External groups for Yammer leveraging Azure Active Directory B2B infrastructure similar to Groups in Outlook or Teams. Our roadmap has us addressing this in Q2 of CY2020.
- We are still thinking through how we would also make External Networks available for tenants in Yammer EU stamp, and don’t have anything to share yet.