Hi. I have 2 facebook acounts, and the first time i went in i logged in the wrong one. Now i want to switch users but don´t know how.

Open your web browser and logout of facebook. If that was insufficient then you will need to also clear your cookies (or just remove all facebook related cookies). When you run photograbber again it should prompt you to log back into facebook.

If you can't get it to work let me know what web browser you are using and on what operating system and I will be able to give more detailed instructions.