Invalid licence key is valid after entering it again
Situation:
I enter an invalid key it then says: Your licence key is invalid, and then jumps back to the enter licence key page.

so far so good, but when i enter the same invalid key it accepts it and proceeds to the installation

I used the same script from topic:
showthread.php?s=&threadid=261704

user: deanbayley who made the script had a solution for it and made an example exe. I already posted in the topic altough its kinda old. So I don't expect an reply.

Any help would be appreciated,

Thanks in advance