If you have ever plugged in an old drive and the disk management said it was an invalid disk. Then this may help.
- Download HxD its a free Hex editor.
- Install and open the problem disk by clicking “Extras” then “Open Disk”
- Make sure you open the right disk! your disk management will list your disks starting with 0, this tool will start with 1
- Also, the default option is to open the disk read only, your going to want to uncheck that when your ready to fix your “Invalid disk”. - Scroll down to offset 1C0(the row) and look in the 02 column. that cell should read “42″ which means Dynamic disk, Change it to “07″ and save changes.
- If your using an external drive unplug it and plug it back in otherwise reboot your computer.
- That should have re initialized the disk and it will now be readable.
- If not go into disk management and take the disk offline then bring it back online.
Doing this will result in No Data Loss!