I just tried logging into my MileagePlus account at united.com and the system did not seem to recognize me, with the message that my password was not recognized. I then tried to retrieve/reset my password but it complained that the username/account #, which was required on the password reset form, was not recognized! Lastly, I tried to retrieve my username/account #, which brought up a form that I had to fill with my email, full name, home address and phone number, and I got the message that "! There is not a MileagePlus account that matches the name or information given." Suddenly I was concerned that I might have been hacked because I had logged in earlier and the system had forced me to choose 5 questions and provide answers (for use if I did need to reset my password); it had also indicated that for security reasons I would have to change my password as well, but after I selected the 5 questions and provided the answers, it just let me into the account without getting to the password change. This glitch may be related. Anyway, apprehensive, I called 1K desk and was told that there has been a major IT problem since yesterday, which has locked many -- apparently not all -- members out. If this has been going on since yesterday, I am surprised it let me book a TPAC flight when it let me in earlier. Fortunately, the 1K desk agent assured me that she could see the booking and everything seemed kosher. If you have trouble getting into your MileagePlus account, then the IT problem I just reported here would be the culprit.