This blog post is probably out of date. If you want to set up Exchange ActiveSync, you should instead consult one my guides:
	iPhone Exchange ActiveSync Setup		iPad Exchange ActiveSync Setup
	iPhone ActiveSync Troubleshooting		iPad ActiveSync Troubleshooting

That's right: I now have five Exchange ActiveSync accounts on my iPhone!

Among the many exciting features of Apple’s version-4 iPhone OS is the long-awaited ability to sync to multiple Exchange ActiveSync servers. The new software, now dubbed iOS 4, can synchronize mail, contacts, and calendars between many different services that use Microsoft’s Exchange ActiveSync protocol, including Microsoft Exchange 2003, 2007, and 2010 and Google’s Gmail service.

Who Needs Multiple Exchange Servers?

You may be wondering if you need this capability. After all, only business people commonly use Microsoft’s corporate Exchange email server, and they tend to only have a single account. But Microsoft’s Exchange ActiveSync protocol is widespread: It is supported by Google Gmail, Microsoft Live Hotmail, and many other services. Contrary to expectations, most people actually do have an Exchange ActiveSync account, and many have more than one!

I currently use no less than five Exchange ActiveSync accounts, and I’m very pleased to have all of them successfully synchronized with my iPhone. I use Google’s Gmail service for personal mail as well as two Google Apps domains (GestaltIT.com and Fosketts.net). I also have two genuine Microsoft Exchange server accounts belonging to corporate clients. It’s amazing to have all of these up and running on the iPhone!

How To Set Up Multiple Exchange ActiveSync Accounts

Setting up a Google account as Exchange instead of IMAP brings additional functionality

It’s really quite simple to set up multiple Exchange ActiveSync accounts in iOS 4: You just do it. Where the old iPhone OS would complain if you tried to enter a second Exchange ActiveSync account, iOS 4 happily accepts them. It’s not clear what the limit is: I set up five Exchange accounts and see no limit in sight!

Refer to my iPhone Exchange ActiveSync Guide for step-by-step instructions on setting up Exchange ActiveSync on the iPhone. I’ve also put together an iPad Exchange ActiveSync Guide.

Note that many folks, like me, had already added their extra Gmail and Exchange accounts as IMAP, since the old iPhone OS had no trouble with these. In this case, you should disable these accounts first to avoid trouble. I decided to turn off my old IMAP accounts rather than deleting them, just in case I needed to fall back to this method in the future.

Look at that! A unified inbox! But why all those other inboxes?

Note that iOS 4 also includes two long-awaited features: A unified inbox and threaded message view. These work great with multiple Exchange ActiveSync accounts, allowing quick access to all your messages.

Quirks and Bugs

Apple seems to have used an incorrect (too short) Exchange server timeout. If you are running iOS 4.0, you should install the Exchange timeout profile (per Apple TS3398) by clicking here from the iPhone and rebooting.

Although iOS 4 mail is much nicer, it’s far from perfect. Most importantly, all this only works on iOS 4 compatible hardware: The iPhone 3G, 3GS, and 4. The original iPhone has to stick with 3.0 and its single-Exchange limit.

Apple may have added a unified inbox, but they made the mail app list even more cluttered by listing everything three times: Once in the unified inbox, again with a line-item per account inbox, and a third time per-account. Odd.

By default, every Exchange account added is named “Exchange” rather than using the email address like other account types. This is ugly, and requires the user to manually change the account name in Settings->Mail to avoid confusion.

It took a while for the Calendar app to synchronize, and it used incorrect calendar names for a while. Also, it seems to only synchronize the default calendar, not any others you might have.

iOS 4 will happily maintain duplicate contacts in one or more lists. I synchronized Address Book with Gmail and Entourage, so all of my contacts were listed four times. It’s probably best to synchronize only one contact list to avoid this situation.

Pay no mind: You won't lose all your Exchange contacts, just those from this account!

When you turn off contact synchronization, iOS 4 pops up a disturbing warning that “all Exchange contacts will be removed.” They won’t. It will only delete the contacts from that one Exchange ActiveSync account.

© sfoskett for Stephen Foskett, Pack Rat, 2010. | How To Set Up Multiple Exchange ActiveSync Accounts in iPhone iOS 4
This post was categorized as Apple, Everything, Features, Personal. Each of my categories has its own feed if you'd like to filter out or focus on posts like this.

This blog post is probably out of date. If you want to set up Exchange ActiveSync, you should instead consult one my guides:
	iPhone Exchange ActiveSync Setup		iPad Exchange ActiveSync Setup
	iPhone ActiveSync Troubleshooting		iPad ActiveSync Troubleshooting

Here’s a quick tip, but a timely one now that the iPhone supports multiple Exchange ActiveSync servers: Although Google supports the Exchange ActiveSync protocol to synchronize mail, contacts, and calendars between Gmail and mobile devices, it is not active by default for custom Google Apps domains. It’s pretty easy to enable it, though.

How To Enable Google Sync

For example, my fosketts.net domain uses Google Apps (mail, calendars, etc) but could not sync with iOS 4. I had to go into the Domain Dashboard to enable it. Here’s how:

1. Navigate to your Google Apps domain’s Mobile Settings dashboard. The URL is as follows, though of source with “example.com” replaced by your domain name.

   https://www.google.com/a/cpanel/example.com/MobileSettings

2. In this window, select the box next to “Enable Google Sync”
3. Click “Save changes” and you’re good to go! You may need to wait a few minutes for the change to go into effect, however.

Note: It took hours for this change to take effect! If your iPhone says “Cannot Get Mail” and “The connection to the server failed”, just wait longer…

You must enable "Google Sync" in the Mobile Settings dashboard before using ActiveSync with a Google Apps account

Google Sync Limitations

Note that Google Sync is somewhat quirky and limited compared to full ActiveSync on an exchange server. Among the notable differences:

1. Searching of server-side email doesn’t work
2. “Delete” = “Archive” by default
3. Advanced recurring events don’t work
4. The number of phone numbers and email addresses is limited

Setting Up Your Mobile Device With Google Sync

Finally, here are a few how-to’s for setting up mobile devices to access Google Sync:

1. Use your full Google Apps email address as your user name (e.g. “you@example.com”) rather than just your username (e.g. “you”)
2. Use “m.google.com” as the Exchange ActiveSync server name
3. Enable SSL
4. Give it some time to sync – changes might not show up right away

Troubleshooting Google Sync

Apple seems to have used an incorrect (too short) Exchange server timeout. If you are running iOS 4.0, you should install the Exchange timeout profile (per Apple TS3398) by clicking here from the iPhone and rebooting.

I had a heck of a time getting this to work with my iOS 4-equipped iPhone 3GS. But it did finally work. Here’s what I learned:

• It can take a while for this to take effect. Be patient and don’t throw your phone through the window.
• Even once it does work, it can be flaky at first. Perhaps it takes a while for all of Google’s servers to recognize the change?
• Even if everything is entered correctly, iOS 4 may not connect. It didn’t seem to want to retry the Exchange ActiveSync connection after it failed (because Google hadn’t activated Sync yet). To get around this, go into Settings->Mail and re-enter the account password. This seems to force a complete retry and opened the floodgates for me.

© sfoskett for Stephen Foskett, Pack Rat, 2010. | How To Enable ActiveSync For Google Apps Accounts
This post was categorized as Apple, Everything, Personal. Each of my categories has its own feed if you'd like to filter out or focus on posts like this.

The iPhone doesn't support more than one Exchange/ActiveSync pairing

One of the major advances introduced in iPhone software version 2.0 was the ability to sync over-the-air to Microsoft Exchange servers using Microsoft’s ActiveSync protocol. This was introduced to much fanfare with the iPhone 3G and is available on older updated iPhone and iPod Touch units, too. Google and NuevaSync also offer over-the-air calendar and contact syncing for the iPhone using ActiveSync.

All of these synchronization options seem like an embarrassment of riches for iPhone users. But, like so many things in life, they’re too good to be true. iPhone OS 2 and 3 can’t sync to more than one Exchange/ActiveSync server at a time! Or, at least, not in the way you’d like.

Note: iPhone OS 4.0 will allow syncing to multiple Exchange ActiveSync accounts! See How To Set Up Multiple Exchange ActiveSync Accounts in iPhone iOS 4.

For the most up-to-date information, see my iPhone Exchange ActiveSync Guide!

This post is part of my series focused on integrating the iPhone with Microsoft Exchange using ActiveSync:

• iPhone OS 3.0 information:
  1. First Look: iPhone 3.0 And Exchange ActiveSync Integration
  2. How To Subscribe To Internet Calendars In iPhone OS 3.0
  3. How To Access LDAP Directories In iPhone OS 3.0
  4. iPhone 3.0 Exchange ActiveSync: Better But Not Perfect
• How To Set Up iPhone Exchange ActiveSync
1. A Few iPhone Exchange ActiveSync Gotchas
2. Can the iPhone Sync With Multiple Exchange Servers?

The Connected iPhone

Let’s back up a minute and talk about how the iPhone integrates with mail, contact, and calendar servers. There are essentially two synchronization engines at work here:

• Like all iPods, iTunes can synchronize your contacts, calendars, and mail account information (though not the mail messages themselves) over a USB connection to the iPhone and iPod Touch. This requires a full copy of Outlook 2003 or later on Windows but works with the built-in address book and iCal calendar on Mac OS X.
• The iPhone can also synchronize some or all components of email, contacts, calendars, and bookmarks using a variety of over-the-air protocols.

Note that when you configure over-the-air sync, you must disable USB sync, and vice versa.

iPhone Email Sync

Configured mail accounts can synchronize email messages in one of six ways:

1. Periodically pulling message content down using the POP protocol – this is what most older ISPs and mail accounts use
2. Periodically pulling message content down using the more advanced IMAP protocol – this is what newer mail accounts, including Gmail, AOL, and Yahoo use
3. Having mail pushed to the phone using a weird combination of hidden SMS and IMAP – this is what Yahoo push mail uses
4. Having mail pushed to the phone using a proprietary notification system of XMPP (Jabber) and IMAP – this is what Apple’s MobileMe push mail uses
5. Pulling or receiving push messages using Microsoft’s ActiveSync technology – this is what Exchange servers, NuevaSync, Kerio, Zimbra, and Google’s over-the-air calendar and contact (but not email) sync use
6. The iPhone’s software seems to support IMAP Idle, which is a realtime message push technology supported by Gmail and some advanced mail systems, but the phone will not use it unless the mail application is actually open on the phone

The iPhone does not support P-IMAP, BlackBerry, or other over-the-air protocols at this point.

The iPhone can sync email messages to any number of IMAP or POP accounts without a problem, but it can only sync to a single ActiveSync server at once. So you can set up Gmail over IMAP, Yahoo over SMS/IMAP, your local provider over POP, a Gmail Apps account over IMAP, etc at the same time as your work Exchange server without a problem. But you cannot set up more than one Exchange server using ActiveSync.

iPhone Calendar and Contact Sync

Calendar and contact information can only be synced in one of (perhaps) three ways:

1. Over a physical USB connection to iTunes (as in the original iPhone 1.0) to Outlook or OS X
2. Using some unknown protocol that MobileMe uses – can anyone identify this?
3. Using ActiveSync to an Exchange Outlook Web Access (OWA) server

Yes, that’s really it. Every over-the-air calendar-and-contact sync system (other than perhaps MobileMe) uses the ActiveSync protocol, including Microsoft Exchange, NuevaSync, Zimbra, and Google’s service.

Now the punch line: The iPhone can only sync to a single ActiveSync server at once. Read that again. Now consider what that means.

So no matter how cool a service is (Google sync, Zimbra), you cannot use it for over-the-air sync if you are also connected to an Exchange server. So even though the iPhone explicitly supports multiple calendars, you can’t sync them with multiple ActiveSync systems. So I guess the iPhone’s calendar system is even more disappointing than I thought!

Pick One ActiveSync Service

The upshot is this: iPhone users much pick one (and only one) ActiveSync service.

• Need to use the iPhone for work? You’ll probably have to use your work Exchange ActiveSync server, and can forget about (usefully) subscribing to MobileMe or using Google sync. Instead, try to sync everything else into Exchange in other ways (like Google’s Desktop app) and then let Exchange handle the iPhone sync.
• A dedicated Mac head? Subscribe to MobileMe and get all of your data there, to be sent to the iPhone.
• None of the above? Google’s new Sync service looks great!

The Big Mystery

There are many mysteries lurking here, but one is really perplexing to me. The iPhone seems to maintain its own set of contacts in addition to any ActiveSync contact store. Although it doesn’t obviously have multiple contacts pools, it must maintain them internally. But you can see that it does in a simple way:

1. Set up an ActiveSync server (like Exchange)
2. Set up an IMAP email account (like Gmail)
3. Add a unique contact on the phone (call him “Steve Jobs”)
4. Add a unique contact in Exchange (call him “Bill Gates”)
5. Add a unique contact in Gmail (call him “Sergey Brin”)
6. Now turn on and off the accounts one at a time

Notice that turning off the Gmail account will, within a few minutes, cause your “Sergey Brin” contact to disappear! Turn it back on and Sergie is back. Now do the same for Exchange and Bill Gates. All the while, your “Steve Jobs” contact should stay put. And this all happens in a single contact list! If you assigned one of these to a “favorite”, their name will be replaced by their number when you remove their account.

So the is iPhone somehow syncing contacts over IMAP? Or does it use some other Google-specific protocol? And how does MobileMe’s contact sync work? Time will tell!

© sfoskett for Stephen Foskett, Pack Rat, 2009. | Can the iPhone Sync With Multiple Exchange Servers?
This post was categorized as Apple. Each of my categories has its own feed if you'd like to filter out or focus on posts like this.