I can't remember what i used as a password. I haven't used Kaos in a long time and haven't a clue what it could be. I've tried all the ones i would use. How can i reset my password?
Can you still boot into the system, or are you stuck at the SDDM screen? Is this question about the user password or root password? UEFI or legacy BIOS systems require different answers, so that needs to be known too. Did you use disk encryption (LUKS)? If it is not LUKS, the safest method is chrooting and while in the chroot run passwd your_user_name and follow the prompts. Other methods are using the bootloader to invoke bash as root.