After helping someone on the problem related to this not that long ago - I decided it might be good to blog about this a bit more; there might be more people that are running into this problem and ...
Updated Jul 01, 2019
Version 2.0
Blog Post
4 MIN READ
Values in unmergedAttributes and msExchUnMergedAttsPT attributes and your ADC replication
Hello Nino,
Thanks for your post!
I wanted to add another case where you can have this attribute populated: Pure Exchange 2000/2003 Admin Groups and Group Membership.
If you setup a one-way CA between Pure 2000/2003 AG and SRS, you may have problems replicating Group membership updates from 5.5 back to AD. If a mailbox from pure AG gets replicated to 5.5 Site A and then gets added to a 5.5 DL in Site B, then this addition will not be replicated back to AD because ADC can't find a match in AD when it searches msExchADCGlobalNames in AD. So it writes to unmergedAtts attribute.
Once you convert the CA to a two-way, the ADC will clean up unmergedAtts attribute and replicate the Group membership back to AD.
Thanks for your post!
I wanted to add another case where you can have this attribute populated: Pure Exchange 2000/2003 Admin Groups and Group Membership.
If you setup a one-way CA between Pure 2000/2003 AG and SRS, you may have problems replicating Group membership updates from 5.5 back to AD. If a mailbox from pure AG gets replicated to 5.5 Site A and then gets added to a 5.5 DL in Site B, then this addition will not be replicated back to AD because ADC can't find a match in AD when it searches msExchADCGlobalNames in AD. So it writes to unmergedAtts attribute.
Once you convert the CA to a two-way, the ADC will clean up unmergedAtts attribute and replicate the Group membership back to AD.