“Upgrade” Distribution Groups after moving from Exchange 2003 To 2010 and find empty distribution lists

When migrating from Exchange 2003 to Exchange 2010, you have to upgrade the distribution groups to 2010 level.

 

Here's how;

 

While co-existing Exchange 2003 with 2010, the “membership approval tab” on the distribution groups property page is all grayed out. You can’t manage any settings in that tab at all. The behaviour is the same for universal and global groups.

 

 

If you make any change to the group (like editing the name), the console asks whether you want to upgrade the object and that you no longer will be able to manage it with legacy Exchange tools.

 

 



 

That raises the question of whether we need to “upgrade” the distribution groups while moving from Exchange 2003 to 2010. I can’t find any information regarding this in Technet. But, to make it work, we need to “upgrade”.
Another efficient way of upgrading the distribution group is to use PowerShell. Run the command below to upgrade. 

Set-DistributionGroup –identity “groupname” –ForceUpgrade

 

In order to upgrade all your distribution groups, run the command below.

Get-DistributionGroup –resultsize unlimited | Set-DistributionGroup –ForceUpgrade 

 

 

After this some cleanup may be required. Deleting the empty DSG's

 

$dls= get-distributiongroup -resultsize unlimited

$dls |? {!(get-distributiongroupmember $_)}

 

When the powershell command returns, it shows the distributiongroups that have no members.

 

Name     DisplayName     GroupType          PrimarySmtpAddress
----     -----------     ---------          ------------------
DSGname  DSGDisplayname  Global,SecurityEnabled    DSGSMTPaddress

 

 

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