This is supposedly fixed as of version 1.216. (Source)

A lot of people are having trouble connecting to the game. The admins are aware of this and will work on a solution after celebrating new year. Thank you for your patience.

There currently is a bug where some accounts do not get logged in properly (or at all). In this case you get to see a blank screen, sometimes with a yellow box in it, when trying to log in. Sometimes you will find that when you use another account you can log in just fine, so this may work as a temporary solution.

If you do have this problem, please send me a PM or post below. Specify the name of the account that's having this problem. The issue is related to the ban system: this means that the cause of the problem could be that you were actually banned. However, this is not true for everyone, so there is no need to panic if you experience this problem. Contacting a moderator will help you figure out what's actually going on. For tips on contacting a staff member, please check the Staff FAQ.

The admins have been made aware of the problem. Our apologies for the confusion and inconvenience.

Extra note from experience [ Benefiting the public from my ban ]

Click Play as Guest to ensure if you are banned or not.

Responses if you click Play as Guest
IP Banned : You have lost connection to the server ;(
Account Banned Only : Perfect Login

Another way to find out if you are ip banned is ... Try logging into another account , if you do not have another account create a new account.
If you are sure you aren't banned talk to Lemodile , and if you are banned talk to Lemodile if you don't know why you are banned .

Another thing i have found out ... after trying so long..
You would disconnect earlier in the game then you did if it was with your flash version .. ( you wouldn't have been able to log in )
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Another way to figure out : If you are using a standalone , please try to use the site to log in.
If the site is not working for you for either account , you are surely ip banned.
Then you would know to contact a mod/admin about your problem

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I hope this post has helped you as I took the time to write this as I have nothing to do right now cuz i'm banned >.< | | | | |
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can this please be stuck so we don't have a gazillion more of these topics

I'm not sure if I'm banned or not, but my sister was on as well when this started

This didnt happen to me.. My screen is just the login page but shaded grey, like its not loading.. ? This has happened before but it was a long time ago and other people said tfm was restarting or whatever..

none of my accounts work

I'm not banned at all. But my account won't work!! Both of my accounts.

Lolalovefox the same thing is happening to me! Im so stressed because I just wanna play.

Name of account: Sickzmedia

Nope, i cant log in, no ban. Just a frozen screen when I press submit.

Lemodile mine aint working, account Grimrice

aiya, It's happening on both my sister's and my accounts! However, the guest account works. My account: NegativePi. My sister's: Raincloudpaw

what do you mean if your ip is banned???

I can play as a guest. Weird.

The guest account option is working but my main account isnt. My account: Phather

Lemodile a dit :

Contacting a moderator will help you figure out what's actually going on. For tips on contacting a staff member, please check the Staff FAQ.

It's gonna be better to privately message a mod rather than post..

obitospain a dit :

what do you mean if your ip is banned???

Just that. If your IP address is banned/blocked.

lol sorry how would I know if its banned

obitospain a dit :

lol sorry how would I know if its banned

You'd probably be best to ask a moderator about that.

Mine is not working.
Same gray/grey shaded screen, and no response of loading at all.
My password and username are in the username and password slot and it's just shaded gray/grey.
I am not banned.
Username: Halosxangels