I installed photoshop in Danish (I'm from Denmark). But I'd rather have the program in English. Therefore I threw the Danish program folder out and put related setting to English and reinstalled. But now it does not work. Can anyone help?
Which version? Cloud? There you can change the intallation language in the Creative Cloud App preferences.
Other versions require a specific licence and serial number.
If Photoshop is installed in several languages you can select the language on Preferences > User Interface