I use Ccleaner regularly.

I ran Auslogics Disk Defrag version 1.4.

After the defrag it gave a message that it had found junk files on the computer.

Is it safe to use the “Scan and remove Junk” option of Auslogics ?

Programs that delete files and registry entries or alter the file structure etc. always have their risk. That's why nearly all of them basically warn you that you're using that program at or own risk and/or request a confirmation after every action.

Some are more efficient than others and "Auslogics" appears to have a solid review on CNET so I assume it's not crap, but, be aware that there is always a boogie-man waiting to get you. It's just a matter of what bed he's under or what closet he's in.

ditto. And once again, zenosincks and I concur.

It's rare, but it does happen.