Help! I cannot install Qubes OS!

[corny]

Are you dual booting ?

Multibooting Qubes

Introduction You should think carefully before dual booting Qubes on your box. Read the guidelines carefully. One problem is that when you dual or multiboot, even if you are using encryption on your Qubes installation, /boot is still unprotected and could be maliciously modified by the other OS, possibly leading to Qubes itself being maliciously modified. The other problem is firmware security - for example the other system could infect the BIOS firmware, which might enable compromise or spyi…

If not, just wipe the drive, refresh and let anaconda delete and start fresh