Hello Atma-Darkwolf,
Thank you for contacting The Settlers Online Support regarding your issue with accessing the game. There are a few things you can do to fix this situation.
1: Make sure you are using the currently available version of your web browser, as an older version may no longer be supported for the game.
2: Make sure you are using the most recent version of Adobe Flash.
http://helpx.adobe.com/flash-player.html
3: Before logging into the game clear your cookie and cache files from the web browser you are using.
http://www.wikihow.com/Clear-Your-Browser%27s-Cache
4: Clear your Flash cache files. You can find the steps on how to do this here:
http://forums.adobe.com/message/4278569
5: Try using another one of the supported web browsers for the game: Fire Fox, Internet Explorer, Google Chrome.
Please be aware that having multiple Flash applications at once will cause lag, server crashes, and flash crashes. Please try to limit the number of Flash based web applications you have running while trying to play the game to have the best experience. Such applications include YouTube, Pandora, and other Flash based games.
If these steps do not work please provide the following information:
-What browser you are using and its version.
-What version of Flash you currently have installed.
-What operating system you currently have installed.
-System Memory in GB