So we are currently working between 2 different forests.

We are still based mostly out of our old one (domain1), however our mailboxes have been migrated and are LinkedMailboxes in the other domain (domain2)

The process is we create the accounts like normal in domain1, we then ADMT them to domain2 and run through the exchange wizard to create a LinkedMailbox, linking back to domain1.


My problem is now, I am wanting to enable the feature in OWA to allow a user to change their password, but it appears that there is an issue with this, where the password change feature is showing the incorrect domain. It's trying to change the password for domain2\user instead of domain1\user

So I had a look around online and found someone who had the same issue here: http://messagingserversupport.com/2012/10/17/unable-to-change-password-using-owa-for-linked-mailbox-in-exchange-2007/

F
ollowing that method, I can successfully get it to display the domain1\user in the password change feature and change the password successfully. 

Now, my question.

I assume that sIDHistory is used in migration for things like locked down folders etc. so that you can migrate to a new domain but keep the existing perms. By removing the sIDHistory, does it mean that this would no longer be possible? 
Is there another way around allowing the password to be changed via OWA, without removing SID history? 

It's weird, because the SID that is in the sIDHistory, is actually the domain1 SID, but for some reason doesn't look up properly in OWA.