SMTP auth server settings I'm using my own SMTP server with SMTP AUTH for sending mails. The greeting looks like:


  250-[...fqdn...] Hello [...fqdn...] [...ip...], pleased to meet you
  250-ENHANCEDSTATUSCODES
  250-PIPELINING
  250-8BITMIME
  250-SIZE
  250-DSN
  250-AUTH CRAM-MD5 DIGEST-MD5
  250-DELIVERBY
  250 HELP  


Unfortunately when configuring user name and password for SMTP (no TLS), Android 4.2 (the standard mail app of the Google/LG Nexus 4) does not seem to expect this: authentication methods aren't supported by server.

On the server, I see Android disconnecting after that greeting was sent.

What authentication methods are actually supported by Nexus 4's mail app?
Probably a bit late to the party, but I'm recording this here for posterity.  My wife's Xperia Z5 Compact (Android 5.?), as well as my own Samsung S3 (4.3) suffer from this same problem.  I've pulled down the source code to the most recent email client, and it appears that the only authentication mechanisms that the native email client supports is PLAIN, LOGIN and XOAUTH2, otherwise the client comes up with the above error message.  As noted in the OP, the mail server is only offering CRAM-MD5 and DIGEST-MD5, which the client doesn't support.  I had to add PLAIN and LOGIN to my mail server (after enforcing TLS), at which point the stock mail client was happy.