Depends, files are usually just "deleted" by changing part of the file name to mark it as dead. Undelete utilities can recover those, if you find yourself in this position DO NOT install anything/create files as this may overwrite the location of the files on the disk. In this case however, she says the HDD was wiped (restore disk?), so the actual data may have been overwritten. There are data recovery services that specialise in these things, but they are NOT cheap, so it's a value judgement.

What if OP's friend used CCleaner to wipe the drive? If so, than it's not possible to recover it.

Unless CCleaner goes to extreme lengths (DoD style), then data is at least partially recoverable, hence my comment about the pro data recovery people - wouldn't want to pay their fees though.

Some reformatting or other disk clean programs write all the hard drive sectors to 0. Meaning no data is recoverable by anyone.

I'm assuming that the "friend" just reinstalled the OS, why would he bother using something like DBAN to fully erase the disk?

This is incorrect. Properties of magnetic media (incl traditional hard drives) mean that data may be recovered even if you zero all sectors. Of course this is only to data recovery pros/labs. This is why DoD have specific protocols for "shredding" drives, usually involving 7 passes containing specific bit sequences.

Her friend was doing it for free, she agreed, it was most likely an accident and you still want her to sue him? Are you gonna suggest her to lie to the court as well?

Is it possible her friend represented himself as a professional? If so, it was a mistake to trust wrong person. If he wasn't a professional, then that's just poor judgment. Lesson learned though is back your stuff up.

One single photo from a professional camera has 14+Mb, while RAW format photos can be 40+Mb per photo! Now imagine how many she must've collected over 5yrs.

Well OP did say it was a portfolio; it's likely she does it for work.

26- Even at 40MB, that still makes 50,000 photos over 5 years. I haven't even taken that many photos in my lifetime.

Never underestimate a photographer. Just for one final I took over 300 photos. Filled up my hard-disk. She may be saving all the photos she took, not just the great ones.

I got 65000+ photos on my flickr. Pro photographers easily take more.

She could have the nikon D800 and be shooting raw. I just started shooting raw and now I need a new hardrive.

Maybe she has one of those DSLR Cameras like Nikon or Canon that take those huge quality photos...

After reading your profile, I have to agree with your statement about you having ADHD...

**Why didn't you have the files backed up? It sounds like you're the incompetence one to me.

*Incompetent ;)

63 - You know, other than typing "u" instead of "you" and misspelling "to" as "go", which is easily done if she's on a phone, those sentences are grammatically correct and your "correction" is pointless.