"Sorry, either that's the wrong password, or the email you entered doesn't have an Xbox LIVE membership. Please try again, or go to Xbox.com/forgot if you need help. Code:80048821"
That is the message I get word for word that keeps me from signing into my account.
I was gaming just fine the night before but when I went to sign into it today I was prompted to enter my information, so I did just that, then I was asked to enter it again which I found odd considering I just did it but I entered my information a second time regardless, and I was met with said message.
Now let's look at the basis of what's going on, I try to sign in, xbox prompts me to enter information, afterwards I am met with the message, all the while I can plainly see that I am signed in through all of this and even looking at my status on the website it clearly says I am "online playing xbox dashboard" so if I had somehow entered anything wrong, would my account be signed in like this? But if I press the guide button to close the message it automatically signs me out.
Now let's pick apart this message, if I had somehow forgotten any of my information...would I be able to sign into the website? No, I wouldn't, but regardless I entered my information as well as very carefully pressing each letter to make sure my password was right SEVERAL times...but to no avail, I then changed my password, deleted my account from the xbox, re-downloaded it and entered my information with the new password several times as well and still I was met with nothing.
Let's go ahead and take a look at the second part of this, I definitely know my email has a membership considering it's had one for well over five years and I was playing 360 even before I got my live account, now I know this couldn't possibly mean being out of xbox live and reverting to silver but let's pretend for a second that it does mean that because even so I'm still good until november of next year.
Now that everything is said and done, this is not a problem on my end, and I cannot sign into my own account on my own xbox, please fix this.
Since you can log in everywhere but you're console, it sounds like Two-Step Authentication was automatically turned on with Microsoft's last security update.
TSA tells the system to use a special password for non-website logins (Xbox, Windows Phone, Zune software, downloaded Skydrive software, etc). While a great method of security, it's not for everybody.
Major Nelson's blog post from early May includes the information on creating an App Password, but also shows on the page where to turn it off if you don't want to use it: majornelson.com/.../using-microsoft-two-factor-authentication-with-your-xbox-live-account