Have you moved to Microsoft’s BPOS mail service but want to use POP3 access too? Well there’s an official undocumented way to do this..
From the PC you set up to run the migration console, start PowerShell, by clicking Start, All Programs, Microsoft Online Services, Migration, Migration Command Shell.
Once the command shell opens, type:
Enable-MSOnlinePOPAccess-Identity username@yourdomain.com
This should enable POP3 access for this user account.