End-user notes on migrating from Exchange to Google Apps

So one of my email accounts is being moved from Exchange to Google Apps and I’ll be summarizing the experience and some tips and tricks here:

The switch-over

It was surprisingly painless. On Monday morning a mail arrived in my MUA (email client) to the effect of ‘you have now been migrated’ and the mail flow stopped after that.

I went to the gmail login page, used my email address and LDAP credentials and whoop, there were all my mails from my Exchange mailbox already and also new mails had started arriving. The new mails were not being sorted into directories/tags though, but more on that later.

One thing that I was missing though was that I was informed that due to a preexisting Google account with the same email address I’d be presented with a ‘migration process’, but that never happened.

Preexisting google account

So as I just said, I did already have an account with important data attached to it that used the same email address (think firstname.lastname@example.com) as the username for Google. I was told that there would be a migration assistant on first logon that would take me through the process of moving that over. Sadly for one reason or the other that never happened.

After I was pointed at the help page about the migration assistant and having a close look at the video on that page I noticed that apparently the preexisting account automatically gets its username changed to something like “firstname.lastname%example.com@gtempaccount.com” in my case – generic pattern seems to be that the existing email address has its @ replaced by % and @gtempaccount.com is appended.

So I tried logging on with that address and my old password that I used for the Google account until yesterday. Lo and behold the migration assistant appeared! It was quite quick and painless to move account data from core Google services from the old to the new account. It also offered to optionally move all the data that I wouldn’t migrate to a new Gmail account (let’s call it new@gmail.com).

There was a snag though about which I had not been informed. I used my preexisting account for AOSP Gerrit and there was associated with special groups. As that is not a core Google service the migration assistant informed me that it wouldn’t be able to migrate that data! I sensed headaches ahead of me.

So I logged on with new@gmail.com to gerrit and all my stuff was still there, that was good news. I didn’t want to use new@gmail.com for attribution though, so I looked at how to fix this. In my case it was surprisingly easy as I was the group admin, so I could simply go to the group view and see that the member list now listed new@gmail.com instead of firstname.lastname@example.com in the member list. All I needed to do was to add firstname.lastname@example.com to the list again and everything was dandy.

In case you are not the group admin or encounter a different non-core Google service you may need to contact the admins of that service to have your account added/migrated for that particular service though.

Exchange server side rules

I am quite fond of server side email filtering rules. Personally I use Sieve on my private MTA (mail server). So for that particular Exchange account I also had created a variety of rules to pre-sort emails directly into directories. That way I e.g. never have to see new mail notifications for high volume mailing lists like LKML (think *bing* *bing* *bing* *bing*).

A quick google search found two interesting open source projects:

I settled for the latter and started fiddling with my virtual Windows7 and Outlook 2007 and then Outlook 2010. Note, that you have to have the .net 4.5 runtime environment installed, otherwise it will crash. I recommend to run ‘OutlookRulesExport.exe -s’ to get the mailbox name, in case your mailbox name is not in the form “foo@example.com” you should encase the whole first line of output in double quotes (in my case: ‘OutlookRulesExport.exe “Mailbox – Ruecker Thomas”‘). Big thanks to Brendan for helping me figure this out!

I imported my rules and found out something about Gmail. It interprets ‘from’ in rules differently. So all my mailing list rules that were based on ‘somelist-bounces@exmple.org’ don’t work. Which is actually good news, as Gmail supports proper filtering by list-id! Quickly redid the rules for the important lists and my inbox immediately looks cleaner.


To sum it up, it’s overall a quite painless transition and there were no major problems. I had actually braced for days without email access etc. I hope this might help someone in a similar position to resolve their issues or help prepare for their move.

To be continued (I intend to update this post in place, so check back for updates!)


Update 1: Figured out mailbox support and updated this post accordingly.

Update 2: Added note about filters.