[Updated 8-8-2017]
How to decommission the old Exchange server, after migration to Microsoft Office 365.
This week I had to migrate an Exchange server to Office 365.
After the migration I had to remove the exchange software, but don’t want to remove the Exchange properties of the cloud users.
The trick in this option is convert the local synchronized users to mail enabled users.
After that you can decommission the old Exchange server safely
Pre requirements :
1 STOP THE SYNC TO OFFICE 365, IN CASE OF AN ERROR!!!!!
2 Create a backup of the active directory ( or export all data to csv : Export to csv )
3 First create a migration.csv file containing all of the users who need to be converted to mail enabled users:
EmailAddress
User1@domain.nl
User2@domain.nl
User3@domain.nl
Download the migration files from :
ExportO365UserInfo.ps1
Exchange2007MBtoMEU.ps1
Execution:
On the on premise Exchange server :
Execute to script .\ExportO365UserInfo.ps1 and Select ‘n’ to proceed
Enter your Office 365 credentials
Here you can read the message in green : CSV File Successfully Exported to cloud.csv
The created cloud.csv file contains all off the Exchange properties off all users you have placed in the migration.csv file
.\Exchange2007MBtoMEU.ps1 <FQDN of on-premises domain controller>
All users from the file cloud.csv are migrated to a Mail enabled user.
When checking the converted users, they are now mail enabled users.
The uses, are active in Office 365.
All off the Exchange properties are still available in Office 365.
It is now safe to decommission the old Exchange server, the online users are not affected anymore.
Check the local user for containing a proxyaddress in Active Directory
Don’t forget to activate the online sync again, when all is OK.