AquaMail not accepting IMAP configuration that default Android email app accepts

[jalan]

My company is using IMAP to access Exchange server shared mailboxes. The configuration works correctly in the default Android email program on my Nexus 5 with KitKat 4.4.2.  The same configuration is not accepted by AquaMail. I really want to use AquaMail because of its more robust handling of folders. Only select folders from within the shared mailbox will be of interest to me.  Here is the configuration:

IMAP Settings

Email Address: sharedmailboxname@XYZ.com where XYX is our company domain

Password: identical to our Exchange password

Account type: IMAP

For example purposes my Exchange username is exchangeusername

Username: XYX\exchangeusername\sharedmailboxname

Password: myExchangepassword

IMAP Server: mobile.XYZ.com (same as Exchange and OWA server)

Port: 143
Security: None

No SMTP - this is read-only sync

This configuration works perfectly in the default Android email app. In AquaMail this results in the following error:

[Kostya Vasilyev]

Please try this:

On the incoming server settings screen, change "authentication" from "choose automatically" to "prefer compatibility".

[jalan]

Yes, that corrected the problem. Thank you.

[Kostya Vasilyev]

Aqua supports several authentication methods (ways to pass the user's credentials to the mail servers) that stock Android Email does not.

Among them is CRAM-MD5, which is the most secure method (does not require the user's password to be transmitted, at all) -- but is often advertised by mail servers and yet doesn't work