For a 3-figure sum they should be able to get your data back if it’s humanly possible, and should only charge if they succeed.
Or, you could just find a professional data recovery firm. After the first run, running Spinrite might well enable it to succeed completely on a second pass.
now its asking for a disk password and wont let me in. This is a good option if you fear your disk is could die completely at any moment, allowing you to recover as much data as possible while you can. What is First Aid Could Not Unmount The Volume For Repair Select Run to initiate the repair. You can then rerun it as many times as you like and it’ll just retry the sectors it has so far failed to read. In a first pass it’ll read everything it can and keep a log of any sectors it couldn’t. If you can boot into Linux of any flavour then ddrescue will clone your hard disc to another. However, Spinrite costs $89, but you get a lifetime personal licence and a money back guarantee if it disappoints. If it was a transient error from a physical jolt or a voltage spike during a write and the disk is otherwise in good health, you can continue using it. It’s far more persistent than any OS or the drive’s internal error recovery logic. Updating boot support partitions for the volume as required. Spinrite can often recover unreadable sectors by doing its own error correction on the aggregate data accumulated from many reads. Invalid extent entry The volume could not be verified completely. Unless you can boot your iMac into Linux and DOS utilities (I don’t know whether that’s possible) you’ll need to take out the hard disk and temporarily attach it to a PC. Take a look at Advanced Hard Disk Tools in the Restarters Wiki. File system repair utilities are of limited use in such cases. It sounds like you’re disk has got physical surface defects.