cgsecurity.org

That is a screenshot of output, when booting the gparted iso, to give access to testdisk & photorec...

What was the partition table type? MBR or GPT?
MBR
Installed where exactly?
On a totally spearate disk.
I don't know what "intermittent access" means.
Sometimes when it boots, the PC detects the disk, other times, doesn't detect it at all.
What kind of errors? File system errors or unreadable ...

Had a boot disk with Win10 about 500gb (3 partitions - 1st boot partition about 50mb - 2nd Main Win Partition about 100gb, the one I am mainly interested in - 3rd small ntfs partition??). Rest was free. Created extended, added ext2 + small swap.
Installed another disk as boot, and installed Win10 ...