My whole code:

Dim $sFilter[0] $sFilter[0]="User"
$UserGroup = GetObject('LDAP://cn=Users,dc=xxx,dc=com')
$UserGroup.Filter = $sFilter
For Each $User in $UserGroup
If Not $User.msExchADC =""
$user.PutEx (1,"legacyExchangeDN","")
? $User.Name + " ExDN cleared."
$user.Setinfo
endif

If Not $User.mail =""
$user.PutEx (1,"mail","")
? $User.Name + " mail cleared."
$user.Setinfo
endif

For Each $Element In $user.msExchADCGlobalNames
If Not $Element =""
$user.PutEx(1,"msExchADCGlobalNames","")
? $User.Name + " ADCG cleared."
$user.Setinfo/
endif
Next

next

I'm trying to clean up a bad ADC replication, and I need to set msExchADCGlobalNames to empty.