Earlier this year I engineered a move of email services from Exchange to Google Apps. Any change of email provider can be quite tricky, but thankfully Google provides a tool to assist in the migration. That tool is “Google Apps Migration for Microsoft Exchange” (GAMME). When I ran through this process I learned a lot of useful bits that I hadn’t seen documented elsewhere. Some seem to be obvious and some are more tricky. The key to remember is that the core of this migration is actually being done by Outlook — not some specialty tool.
- You must use 32 bit Outlook — If you’re an IT person, you probably run a 64 bit OS and all the apps you can get in 64 bit, like Office. If you run Google Apps Migration for Microsoft Exchange (GAMME) on your fully 64 bit personal machine — it will fail.
- Remove any possible Outlook Plugins — Anything, and I do mean anything, that plugs into Outlook will cause a problem. This includes any antivirus and backup/sync software. I ran into this issue in the form of strange migration issues. Emails lacked recipients, or the recipients were mangled (e.g. Name but not email address).
- Skip the laptop, run GAMME on a server — The best advice I can give is to simply skip any testing or transfer on laptops and go directly to a server — even if it is a small migration. I fired up several Windows EC2 instances to run my testing and migration.
- Setup all the accounts well in advance of the migration.
- Run a full migration WAY in advance — This is especially important if you use a hosted Exchange provider, you may find that your exchange server limits the number of users you can touch at once. I ran a test with 25 of our 75 users and everything was fine… until the real migration came.
- Migrate most of the mail in advance — GAMME is slow, even with a 100 mbps connection, it didn’t use any significant bandwidth. My migration (partially because of user limitations and partially from the download speed) took two to three times longer than I expected. So instead of waiting until the switch over date for a full box migration, move it in steps. Several weeks in advance run a migration that goes up until a specific date, that will move potentially years of legacy email. Then on the switchover weekend you have only a few weeks to a month of email to move — instead of years.
- Warn users that the LAST thing to migrate is Inbox — As counter-intuitive as that might sound, I found the the last set of email for GAMME to move is the Inbox. Of course the first thing the users look for are their inbox messages.
With the exception of the speed at which Google Apps Migration for Microsoft Exchange (GAMME) moves email, I’m quite pleased with the tool. It is fully featured and has a bunch of smart options that give you a lot of flexibility in your migration. I would have liked to have a few more options on which folders to move first, or some sort of priority system, but it’s not strictly necessary. If I were to run another migration I’d use the tricks I learned from this last one (and have dutifully recorded for you) and it’d be a complete breeze. Dealing with users used to Outlook, and teaching them about Gmail afterwards is more than challenging enough on it’s own.