Deep scanning never ending scan

I have been running a deep scan on a 500 GB HP Personal Media Drive HDD connected directly to my PC motherboard.

The scanning has now been running for more than 72 hours and for the first 2 days there were progress. For almost 24 hours, the progress counter has shown 92% and the remaining time has increased from 3 to 5 hours.

I can see the drive from Windows but cannot open it to see folder structure or files. When starting the PC, the BIOS has 2 times warned med that a drive was in danger of crashing and should be replaced.

Will I be able to see and recover what's in the first 92 % if I quit now?

Any other advise on how to recover 10 years of family pictures for a friend who actually used this drive as backup while reinstalling his Windows OS?

I have also tried the ddrescue and photorec programs from gnu.org, but these only recovered files until 2009!

Please see attachment for a curent screen shot of Recuva status.

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