The external loads onto the computer (have tested on Mac, Windows, Linux and the netbook being Windows aswell) fine but won't mount. I've used Phoenix (and PhotoRec) to scan and the data is still intact (not sure if 100% fine). After many hours of research, I think the ntfs partition table is corrupt. I've tried Test Disk (as well as PhotoRec) and MiniTool Partition Wizard to repair and recover the table. Noting this, I could be wrong yet can't find another plausible reason. My other drive (exactly the same with almost cloned data) stuffed up quite recently but managed to fix it with Chkdsk after also many hours of research (and that took days to complete). Windows says the drive needs to be formatted to be used, Mac won't mount nor allow 'Repair Disk' in Disk Utility even though it shows there (couldn't mount it via Terminal), and Linux said it couldn't mount regarding something about error 2 (I tried ntfs-3g, ntfsfix and another tool I think that I can't remember if I did). My Mac uses a combination of MacFuse and Tuxera NTFS to mount NTFS drives and that hasn't had a problem - another NTFS drive works fine so I ruled that out.
This is all a rundown of my efforts. Have I missed anything? Is there any way to repair? I think I can recover but how can I be sure that I'll get everything (100s GB)? Phoenix sorts the files out itself and only the Raw Recovery and Formatted Media... & earch Lost ... work from Drive Recovery Tab. It used to all work normal with the drive. TestDisk/PhotoRec is now asking for a password on Mac so can't use it but works fine on Windows. If I remember anything else I'll update but I think this is all I've done for now. I can't continue any work or projects until it's fixed so I'm lagging behind schedule and I'm not a person who does. You're help would be sincerely appreciated, thank you in advanced.