Question : how do I remove deleted accounts from exchange 2003 SP2 public folders?

One of our clients has an exchange server that is attempting to send meeting requests to users that are no longer part of the domain.  In my investigation, I went into the ESM, opened the properties of the public folder that they schedule with, and I can see two accounts that are unkown (e.g. only show their SID).

When I try to remove these accounts, I am told that they cannot be deleted due to inheritance issues.

So, I went into regedit and added HKCU\Software\Microsoft\Exchange\ExAdmin\ DWORD_REG: ShowSecurityTab and set it to 1 (per MS article) so that I could go to the top most folder to remove these users from the entire exchange store.  Unfortunately, this page tells me that I cannot remove these users, either.  The same reason is given, that the folder is inheriting from it's parent and I need to turn that off.  I don't want to turn off inheriting unless I absolutely have to.  I'd rather remove inheritance on just the public folder in question.  Unfortunately, when I go into the Administrative Rights, there's no checkbox to disable inheritance.

Any thoughts?

Answer : how do I remove deleted accounts from exchange 2003 SP2 public folders?

Use PFDevadmin to remove it.