At times, when I hibernate my Dell Latitude e6400 with Windows 7 (64 bit), the laptop screen goes black as it should, but then it takes several minutes before it powers down. Then, when I attempt to "resume," Windows boots up from a fresh startup, with all my work lost, and tells me that it's recovered from a serious error. What can I do to resolve this problem?

Other background info: -I got a new hard drive with plenty of space about a year ago; I only use a small fraction of that space. This sometimes happens when I don't have any programs running at all. If it's relevant, I do have Dropbox and OneDrive running in the background, though.

-The problem usually occurs when I hibernate just after I unplug from an external monitor to bring my laptop home, but I believe it happens at other times, too.

Problem signature:
  Problem Event Name:   BlueScreen
  OS Version:   6.1.7601.2.1.0.256.4
  Locale ID:    1033

Additional information about the problem:
  BCCode:   1000009f
  BCP1: 0000000000000004
  BCP2: 0000000000000258
  BCP3: FFFFFA80036DEB50
  BCP4: FFFFF80000B9C510
  OS Version:   6_1_7601
  Service Pack: 1_0
  Product:  256_1