I noticed today that I needed to confirm an email from firefox to allow sync to work again. This however did not turn up so I refreshed the link to get them to send again and still it did not turn up. I checked my spam logs and discovered that every time I requested a new email a log entry appeared. I white listed the domain and IP and received my confirmation email. The reason why the spam filter caught the email was that the email was from an amazon aws site and not mozilla.org. Personally I think that the email address return path looks really dodgy and I would recommend that mozilla use their domain for firefox sync emails rather than the following: 0101015963aexxxc-xxxxxxxx-xxxx-xxxx-xxxxxx-97c4bbd9cdf8-000000@us-west-2.amazonses.com I have placed xs in a few of the sender address in case the front code identifies myself. However you can see it does not look like a very legitimate email. If you look up the address there is nothing to link it to firefox or mozilla. http://myip-address.com/ip-lookup/a27-111.smtp-out.us-west-2.amazonses.com I think that this needs to be rectified but not sure who to email contact for this so have posted here.