Hello again everyone,

For the model names:
- WD Red I want to fix -> WDC WD60EFRX-68MYMN1
- WD Green I use for tests first -> WDC WD15EADS-00P8B0
I'm not confident enough yet to fiddle with my WD Red, but I made a lot of progress learning how to use WDMarvel with my test HDD (the WD Green in bad health that I don't care about).
Here is what I did so far with the test HDD:
- Isolate the HDD from Windows -> Disable the HDD and all SATA controllers in Device Manager (one controller can't be disabled, probably used by the system drive?), Disk Manager don't see the HDD anymore so I think we are safe
- Select the right HDD in WDMarvel -> In the "IDE/SATA controller selection" section, select in the menu on the right the SATA mode used by the motherboard ("SATA/AHCI" in my case) and select a SATA port in the grid, then in the "Drive" section, click the "Detect" button to check if the port is for the right drive (Windows gets neauseous if you stumble upon the system drive, I rebooted just in case...)
- Once the right port is found, check "Lock current device" (not sure why, I suppose it's so WDMarvel gets some sort of exclusive access to the HDD I guess?)
- Backup the firmware
For the backup I used diybit's method:
- Click on the menu "S/A operations > Modules operations"
- In the new module window click on "Modules > Read all" (modules are dumped in the folder "Default\Modules" in WDMarvel directory)
- Once the operation is finished click on "Modules > Check all modules"
- Close the module window
- Click on the menu "ROM > Read ROM" (ROM is dumped in file "Default\PZU\Flash.bin" in WDMarvel directory)
The health of the WD Green seems bad as expected, because the module 6F ("Overlay") have an invalid CRC. But I use it only to test WDMarvel anyway so I don't care.
After that I used legija's method, I clicked on the menu "S/A operations > Restore points" and on the button "Create point". Apparently it does the same dumps, but with more data and neatly packaged in a ZIP archive in "Default\RestorePoints".
So far I think I finished all the preparations, but I'm not sure what to do next. I found in the menu a "Format unit" like diybit suggested if someone could confirm this is the right option, and I also found 2 "clear SMART" features that looks rather explicit:
- Defects > PDList and format > Format unit (Cmd)
- Heads > Clear SMART, defect lists, Translator
- Other > S.M.A.R.T. > Clear S.M.A.R.T.
Could you tell me which one should I choose?

Also the WD Green as been a good test subject until now but it doesn't have the SMART error I try to fix on the WD Red. Do you have a way to check if SMART data have been reset? If not well at least it will confirm what I do in WDMarvel don't kill the HDD right away.