Hello all -
We have three internal domains, two which contain the current logon accounts and the new one to which we will eventually migrate which currently just holds the new Exchange 2010 server and a DC. We are migrating from Rackspace hosted email. All of my top-level users have accounts in up to six external (email) domains which they have configured on multiple devices as well as home computers. Rackspace does not force them to ever change a password so the solution was workable. We have now begun the migration process but after having configured the internal email accounts for these users by giving their one domain logon account full access permissions and send as rights, we are discovering that we cannot configure all of these accounts (either via ActiveSync or IMAP) on their external devices (especially the Apple ones) as it specifically looks at the fully qualified logon account and sees it as already configured.
I had considered just using the accounts in the Exchange domain and just setting the passwords to never expire but then we'd never pass another audit.