External USB drive forgot that it´s full of data

I somehow managed to mess up my external USB drive with a few hundred gigs of data. Some of it is junk anyway, but there are also some project files I really want back.

Here is what happened -
I´m currently at my familys house and brought my USB drive with me. It was connected to my work laptop all the time and also worked when I hooked it up to my mothers PC to burn some files to DVD.

After the DVD was finalized I switched it off, without noticing that Nero was set to compare the DVD with the source files. I didn´t think about it much because it was just a reading process, no writing process, stuffed the drive in my bag and went to a friend.

There I hooked it up again, XP installed some drivers (it has a built-in USB hub) and then, well, not really much more. It showed up as an unnamed drive in the Explorer and Windows wanted me to format it. Err... NO!
I thought about some weird compatibility issue and just put it back in the bag.

Now I´m back at my work PC and it shows up as an unnamed drive here, too. Plus I don´t really have much diagnosis options since my work PC runs only a limited user account.

Any ideas what I can do to recover the data? The hard drive is a TrekStor model and was formatted with NTFS. I always thought this file system wouldn´t break so easily.

Additional Spam:
So, I´m at my mothers PC now - I started with a tool names TESTDISK, but it doesn´t make sense.

It shows the name and type of the partition, but can´t access the files in it. After all syncing MBR and whatnots Windows still doesn´t want to access the drive.

Well, looks like FindNTFS can at least see the files and write to another drive. Have to buy a new hard drive tomorrow then, not enough space here.

Jam it back in, in the dark.

Plug in your hard disk.

Start -> Run -> diskmgmt.msc

What do you see?

How ya doing, buddy?

Will do as soon as I can plug it to my own PC. My guess it will show as a partition without file system or fucked up NTFS.

This thing is sticky, and I don't like it. I don't appreciate it.

So here is the screenshot - it´s in german, but it doesn´t read so different.
The drive in question is "Datenträger 3".

New drive is coming this week. I´ll just copy everything from the lost partition with FindNTFS.

I am a dolphin, do you want me on your body?

Yeah, it's showing without an NTFS partition all right, and it's marked "Active". You can always try rightclicking on it and see if there's an option to 'convert' it to NTFS, but since you have another drive coming, it's probably not worth the data risk

Most amazing jew boots

I already partially restored files with FindNTFS - although it´s not really user-friendly it works fine and the data looks unharmed. So I´ll keep my fingers off it for another two or three days.

I wanted to clean up the drive anyway, using it as a regular hard drive was not the best idea I ever had.

What kind of toxic man-thing is happening now?