We are having this same issue with 7262, but with iOS. All passwords are rejecting.

With 7269 on a test vm it works with outlook on android, but we're not really willing to take the risk to install beta's on a 22k+ accounts production server.

Maybe it also works for your iOS issue ?

It would be good to have this backported to the current "stable" versions, our customers are urging us to fix this or will find another service provider...

edit: 

"you CAN NOT downgrade back to a previous version due to the extensive file system changes that were made. "

This is mostly why we can't risk to update our prod server. We have snapshots on our NetApp filer but if the file system changes are related to the user's data, if we rollback a snapshot we would have to rollback domains data too and lose content received while running the beta.

It would be nice to know exactly what changes are made to which files when installing the beta.

@Sébastien Riccio

-Domain's sharing.json was changed pretty significantly

-mailbox.cfg (a binary file) had 2-3 new fields of data put in them. Since this is a binary file moving this to a PRE-BETA system would cause exceptions, this is the main reason for no-downgrade.
-There might be other files touched, some have been removed like root.cfg, completely irrelevant, folders.json was able to take the burden that root.cfg served.
-Mail transfers (new messages, moving messages between folders) is now delivered immediately to each user's MailProcessing folder where a host of new files are used to QUICKLY perform user actions. Generally, once a couple seconds pass mail data gets pushed into the user's mailbox.cfg and grp's. (THIS IS A HUGE SPEED IMPROVEMENT FOR SM)

Technically speaking if a rollback absolutely had to happen, if sharing.json was removed and mailbox.cfg was removed for all users it should be able to recover. However user's would lose shares, read statuses, flags, etc.
I don't at all recommend rolling back for any reason though, as there could be all sorts of untested behavior occuring.

Hopefully I answered any open questions about some of the technical changes we made and how we are utilizing the files.

PS/EDIT: We had to make some pretty significant structural changes to how we serve EAS data, it would unfortunately not be able to be something we can scoot back into pre-beta. We are not recommending BETA for production yet, but I believe the next release or 2, we would lift that warning. I know about 2-3 people with a live environment right now but (including us) but none are very large from the looks. If anyone with a large system WOULD like to move to a beta (maybe not right now) I can work directly with you on any issues that might pop up. I'm spending my time working directly with beta users.
 

Matt, as always, you can DM me and I can see what I can do to help with our system.

Though it would be nice to have a stable RTM release of SmarterMail that has EAS working... Right now, if a customer buys EAS, they are SOL for setting it up on their mobile device, which puts us in a bad spot as we are selling a product that doesnt work.

I just encountered the same issue. Client can't connect to his EAS account using Outlook Mobile for Android