I login with my Windows name and password but my account is invalid. What does this mean?

Answer: 

All CC domain Windows passwords have a maximum age of 720 days.  A warning is issued 10 days before this expiration.  This warning will only be seen upon logging in to a Windows computer within this 10 day period.  So, if you have never accessed a Windows computer, your account password could expire without your awareness.  If you believe that your Windows password has expired, please see the information about resetting passwords located here.

You may also receive the "Invalid Password" error due to another TSO policy.  We have a policy in place to lock a Windows account after 5 invalid login attempts.  This is to secure against brute force attacks on our users' Windows accounts.  In this case, the lockout duration is 60 minutes.  In addition, since our email migration to Zimbra (and since Zimbra authenticates with a user's Windows password), we have noticed that certain email client settings have been locking users' Windows accounts.  If you use an email client (i.e., Outlook, Thunderbird, etc.) and save your password to access Zimbra mail, this can cause a Windows lockout as well (due to corrupt packets, miss-typed password, etc.).  We recommend not saving your password when accessing Zimbra mail with an email client to avoid lockout.