How do I change my cmd.exe to English?

Execute

chcp 437

in the cmd prompt.

For example:

C:\Users\javaserv> chcp 437
Active code page: 437

It depends on how your Windows is localized (I'm not familiar with Dutch Windows specifically). Look at the following folder:

c:\Windows\System32\nl-NL

If you have the file named cmd.exe.mui there, rename it to something else. Your command prompt will be in English mostly (all text coming from the cmd.exe will be English, but some error messages are coming from other sources and will be in Dutch.

If you don't have such folder, or if cmd.exe.mui is not there, it means your cmd.exe (command prompt execuable) has its Dutch strings built in, so you cannot change it to English easily.