It is possible at that your e-mail address has been cloned by nefarious parties who sometimes use automated bots to attempt to access e-mail accounts for fraudulent or spamming purposes. Most mail providers do a random check to authenticate you are who you say you are and will challenge you to provide additional proof of existence using the bit map verification (remember that on PPRuNe) particularly if you have made a number of password changes or requested such changes over a short period.
Hotmail are not particularly helpful in sorting the mess out if you have been victim of this sort of activity or if you have erroneously been flagged as a threat.
Caco