When you migrate Exchange Server 2010 Public folders to Exchange Server 2016, you may come across the following error on the public folder mailbox sync. This error can be found on the report of the sync report.
[EXCH2016] Public folder “/Public Folder/Sub Folder” could not be mail-enabled. The error is as follows: “No mail public folder was found in Active Directory with object ID ‘78340878-dc63-40da-be4b-d24ec47c55c4′”
This can be resolved by disable-mailpublicfolder command by disabling the publicfolders one by one.
Disable-MailPublicFolder -Identity “/PublicFolder”
If you find you want to disable mailpublicfolders in bulk, you can use recurse switch and point the parent public folder. Here is the command to do so.
Get-PublicFolder -Recurse -Identity “/Projects” | Disable-MailPublicFolder
In this command /Projects is the parent folder where that folder and subfolders of Projects are mail disabled.
I hope this info would help someone looking for resolution for the above error. You may send me a note if you want more info or your questions.