Aug
31
Written by:
Jason Taylor
8/31/2011 9:23 AM
Migrating Exchange to Office 365 Tips
During our company wide adoption to Office 365 we ran into a snag and although it was simple to overcome once we discovered the right steps, it was a challenge at the time. To help others with their migration from Exchange to Office 365 we have put together a few tips.
Background
Our migration was from Exchange 2003 SP2 to Office 365 Plan E3 and involved about 20 mailboxes. It was determined ahead of time none of the mailboxes would exceed the size limit of Office 365, and RPC over HTTP to our Exchange 2003 server was configured and tested which is a requirement of the Office 365 web-based exchange mailbox migration tool.
The Problem
During the initial setup of the Office 365 instance we had created 3 of our eventual 20 users. This fact turned out to be what got us in trouble. When we first started the migration, all of the mailboxes except these failed. We received the following error on each of the other mailboxes:
"A parameter cannot be found that matches parameter name 'TargetAllMDBs’".
It was not more than a few minutes before we drew the conclusion the mailboxes must exist first in Office 365 first, so we created the mailboxes.
Tip 1: Create all your users mailboxes in Office 365 first. Use the bulk upload tool if there are many.
So now we thought we were on the right track. Our Exchange tools in Office 365 included a “Migration” which was “in-process” and not “completed” for three of the mailboxes, and 17 more to migrate. We did not “Complete” the original migration thinking we need to finish it later or it would complicate things worse.
Tip 2: “Completing” an existing migration that did not work, or does not include all the mailboxes, is not going to make things worse. Complete all migrations before starting a new one.
A new migration will include any mailboxes which need to be synced. The complete process just checks for unsynchronized exchange items one last time and is definitely the last step before changing your MX records in DNS. However there is no reason to avoid completing if you are having problems.
The additional migration continued to fail with the same error. We created new migrations and tried again several times over several days. Finally we mustered up the courage to “Complete Migration” on the original failed migration and start with a clean slate. Our courage paid off because the very next migration went smooth. All users confirmed healthy synchronization.
To confirm our eventual approach and conclusions were the best path we consulted the tech assigned to our Service Request (Joshua with Microsoft Online Services Technical Support). He confirmed after consulting some other colleagues that indeed these two tips are the recommended path and will resolve this problem in many cases.
We hope these tips make your Migration to Office 365 a simple process.
Copyright ©2011 Jason Taylor