After the recent iOS 6 update, I started experiencing a really annoying behavior when replying to all on an email. Every time I hit reply-all on an email I would get a copy of the email. After asking my coworkers about the issue the default answer I got from everyone was…
“Go into Settings – Mail, Contacts, Calendars and turn off Always Bcc myself”. I don’t use that feature, so I expected that to be off (unless a bug in the iOS update changed it) and it was.
I couldn’t figure out what was wrong. After some search online, I came across an article about issues with Outlook 2011 on Macs running Lion. This got me to thinking.
When I first started at Catapult my email address was David.Rowe@CatapultSystems.com, but soon after I switched my primary email address to Dave.Rowe@CatapultSystems.com, because I go by Dave these days. When I set up my iPhone I used my UPN which is still David.Rowe@CatapultSystems.com.
When someone would email a group of people including me, (Dave.Rowe@catapultsystems.com) I would Reply-All, but my my iPhone ActiveSync client would think that David.Rowe@catapultsystems.com was sending an email to another user named Dave.Rowe@catapultsystems.com. Of course these two aliases belong to the same mailbox, so I was being copied on every email.
Here you can see that I hit reply-all to an email from my personal account. Not only is my personal account email in the To: field, but my Dave.Rowe@catapultsystems.com was also in the Cc: field.
To prove this theory, I changed my email address in the settings on my iPhone and attempted to respond to the same message.
It didn’t even offer the option of Reply-All.
In conclusion, to resolve this issue change your email address on your iPhone to match your primary email address in Exchange.
BEWARE: This will force a resync of all of your email, calendar, and contacts.
This is a bug that didn’t exist before iOS 6. There are a number of bugs in the iOS 6 implementation of Active Sync. Steve Goodman just posted a blog on the iOS 6.0.1 update. As one of my coworkers has said, maybe I should switch to Windows Phone and avoid all of these issues. 
And, I just confirmed that this bug still exists in iOS 6.0.1.
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