Disk with important stuff is "blocked"?

MacMasterMac

Commendable
Feb 28, 2016
59
0
1,640
I have always had a recovery disk (D) with 60gb. It was always empty and I never used it.
But today I decided to put some files on it. Now the disk is locked! http://prntscr.com/j527ez

When I look online, everyone is formatting them, but then I will lose my important files!
Is there a way to get it back with every file and folder that was on it?
I do not want to install a recovery software
The disk is in "RAW" for some reason?

Thanks!