A system and method for handling e-mail address mismatches between the address contained within a user's certificate or certificate chain, and the account address actually being used is disclosed. In order to resolve address mismatches a canonical or generic domain name or user name may, for example, be used as a lifelong address of a user that is contained in the user's certificate. Upon detection of an address mismatch, the system and method disclosed herein may automatically re-check the certificate or search for a certificate containing the canonical or generic domain name and/or user name to attempt to resolve the mismatch. This mismatch resolution is preferably transparent to the user and occurs automatically. The canonical or generic domain and/or user names that are available to the device may be typically controlled by IT policy that is in place on the system for the device. While this system is suitable for any type of electronic messaging system, it has particular applicability to systems that use mobile wireless communication devices with electronic messaging capability.