I'm working on a multi-domain Exchange 2016 configuration running on Server 2012 R2. Since it is multi-domain we use a third party control panel to manage the users. The issue may not be due to the 3rd partly control panel but shortly after an update to the control panel we noticed the SAMaccountName was being created completely different than about a week ago. The vendor reported that there is nothing in their product to change the default way Windows created the SAMaccountName. We noticed since Folder Redirection uses the SAMaccountName to create the folder names. I have done some google searching but can not find anything on what could be altering the default way Windows creates the SAMaccountName.
Any ideas would be greatly appreciated.