exmsft.com provides email services for ex-Microsoft employees.
If someone requests an account but is unable to send from their @microsoft.com email address we ask that they provide one or more references from existing Microsoft employees. If you’ve received such a confirmation request from the exmsft.com administrator (currently Leo Notenboom), that’s all that’s going on.
We simply need informal confirmation that the person requesting the exmsft.com account did, once upon a time, work at Microsoft.
Thanks for your help,