We're in the midst of a mail migration between two companies. For a pilot with mail migration we want to disable Outlook WebAccess for a specific group of users. The mail is migrated to a different AD domain, but during the pilot the users still need to log in with the credentials from the old domain. Due to these circumstance we can't use the Exchange Feature to disable OWA because by using this setting the cannot use the webmail in the new domain.
The idea now is to disable access to the old OWA environment by setting Deny rights in the ACL of the OWA IIS site, but we cannot find any tab or directory to set these deny rights. The /exchange virtual folder is redirected to '\\.\BackOfficeStorage\prc.nl\MBX' but browsing to this folder is not possible. We have a frontend/backend configuration in place.
Any help is appreciated.