Obviously there is a bug of some sort and I would like to understand it and fix it, so here goes:
Somehow the message box is picking a crazy font from the system, but I can see that the box underneath is using the correct font, and is readable. So how the heck that one particular message box got a wacked up font, no idea... but I'll have a look at the code.
For now, I can confirm that you DO have an existing license and It looks like you successfully registered Filtryg back in January. I guess it worked okay back then on that particular machine?
So, this is on a new computer installation, and online registration is failing... and also giving you a crazy box that is not readable? Right?
What OS/Version is this happening on? I am guessing Windows? Can you share which version?
Are you able to login to your mok.com account? Maybe you got the login info wrong?
Here is what the box should have looked like: