Paragon Hard Disk Manager 15 asking for password when I boot from CD

I have a genuine CD with Paragon Hard Disk Manager 15 on it. I often boot directly from the CD without any problems. However, today I went to backup my desktop computer and when I attempted to boot from the CD it puts up a big blue screen with the Hard Disk Manager 15 logo at the top and then a box appears in the centre of the screen asking me to enter a password. This has never happened before. Why is it doing it now, and what is the password? I don't remember ever having set one up.

Any help appreciated.

No idea. A CD is read only so it can't change. If the CD worked fine for a while and then stopped the changes have to be in you system. Encrypted some partitions? Things like that? You can protect a backup with a password but I've never seen such an option while creating a recovery medium. And I created a lot of those by now.