TS26, welcome to the forum.
This error message means that your hard drive has failed and should be replaced. To make certain, you should go into the BIOS (tap F10 continuously at HP logo) and run the S.M.A.R.T. diagnostics. This will tell you if it has failed.
Please click "the Thumbs Up+ button" if I have helped you and click "Accept as Solution" if your problem is solved.