My D:\ partition has disappeared twice this week. Why/how to fix?

[desert2som]

My D:\ partition (which I used to store downloads and data) completely disappeared a week ago on Friday, then I was able to recreate it and reload my data from an external backup, and then this Friday (one week later), the D:\ partition completely disappeared again. My first question: WHY is this happening . . . twice? And this time, can someone instruct me if there's any way to recover my D:\ partition and all it's data without having to create the D:\ drive from scratch and then reload it from an online backup service (which takes 3-4 days to fully redownload).

Here's a screenshot of my Disk Management information: (My D:\ partition is the 300.10 GB "free" space)


So, to recap, I want to see if I can recover the D:\ partition and all the data on it. (If not, I know how to recreate the D:\ partition from scratch, and I can redownload the data from my external source.) The BIGGER question is: WHY is this happening (twice now in just one week) and how can I be assured that once it is fixed, it won't be happening again to me?

Thanks!
Mike

 

[desert2som]

Also, based on someone's suggestion, I did run a successful "Diagnostics" program on my full system, and it found no errors. Just wanted to let you know I had just completed that step too.
Mike

 

[bobafetthotmail]

There are programs like AOMEI partition manager that should be able to recover lost partitions like that. (in the wizard menu, "recovery partition wizard"). Then doing a full "disk check" of the partition (and the rest of the disk for that matter) is a good idea. THis tutorial.

I would also download and run the hard drive's manufacturer diagnostic tool. It is specific for a few model of hard drives, not a generic one. You need to search in google with the model number of your hard drive, open Start menu and type "device manager", select the entry with this name and look in the section about hard drives, it should list the drives by their model name.