Working HDD not showing up properly/not accessible

[gstdiandre]

So this morning, I remembered that the drive I use as an external HDD (via USB) has a Vista partition on it from the time when said HDD was on another laptop. I used to boot it from time to time just for fun but I hadn't done it in a long while. Since I was planning to delete the windows install from it and wanted to know what programs/data I should be looking to export before format, I decided to boot it again as an external HDD.

 

I boot it up, I get the Vista loading bar then blue screen with a STOP code. I thought it must be some driver error or something of the sort. I try again in safe mode, same BSOD. At this point I don't look further into it since the partition was for another laptop and decided to just reboot Win 7 from my main drive.

 

When rebooting, the drive just stopped working. When plugged, it would show up after 20-30 seconds as Local Disk (D:) but remains inaccessible with no size information or anything of that sort. I proceeded to install the drive on my second HDD bay to see if it's a faulty external HDD case. Same result. Drive shows up, can't be read from, chkdsk d: stays stuck on a blank line (doesn't even retrieve drive info, let alone start the check) and diskmgmt.msc keeps loading endlessly.

 

The thing is, I know it's only a logical error and that there is no lost data because 1) No physical damage was done to the disk throughout this entire process, I've moved drives around countless times and 2) I went back after the drive became unreadable and tried to boot Vista again. It worked. Same Vista loading bar, same BSOD. The partition still works.

 

But I don't know why my OS can't checkdisk the drive. So help would be appreciated  Tell me if you need anymore info.

 

Update: The drive is showing up as a device (Toshiba+model number), but the drive itself is still inaccessible/uncheckable. 

 

Some Minitool Partition Wizard screens (Check file system doesn't work, starts and remains stuck): 

https://imgur.com/a/GCC6Hmc

https://imgur.com/a/XnfxDP1

https://imgur.com/a/O2k9pb9

[LulaGreen]

It seems file system of the drive has been corrupted. In this case, the best way is to recover data using data recovery software, and then reformat the drive.