Creo 3.0 Student Edition License says "Succes!" but also "Invalid file or format"

Good day,

I'm trying to activate my Student Edition of Creo 3.0 with the following manual:

http://apps.ptc.com/schools/references/install_creo3_unistudent_standard.pdf?_ga=1.113291907.521497967.1476201064

But shortly after I click on "Install License" and login into my account, he tells me that it was succesful, but also that the license is an invalid file or has an invalid format, what makes it impossible to click on "Next".

I tried it several times, disabled all kind of firewalls, rebootet, deleted the license folder, nothing works.

Any ideas?

Lukas