To correct this, open the Server Certificates tool in Windows and navigate to the following sub-directory in the tree:
Certificates (Local) -> Enterprise Certificates -> Certificates
Any certificates located here will have been created prior to the server having been moved to its current domain. These must be deleted before attempting the new install. Once removed, the Aegis installation should complete successfully.
When Aegis is being installed on a server whose Domain Membership has been recently changed, the installation is likely to fail due to a password encryption failure. The password encryption failure is a result of pre-existing Enterprise Certificates, which point to the domain that the server was previously a member of, rather than its current domain.
In such a case, the installer will fail with the above error. Once the error is acknowledged, the installation will roll back and exit.