Annoying bugcheck - prevents laptop from going to sleep

I have an Apple MacBook Pro Mid 2012 (i7 3720 QM, 8 GB RAM, NVIDIA GeForce GT650M) and running Windows 8 Pro 64-bit via Bootcamp. Over the past couple of days, it doesn't sleep when I close the lid (it stays on) and on opening the lid, it shuts down! I was digging through the Event Viewer and found this error:

The computer has rebooted from a bugcheck. The bugcheck was: 0x0000009f (0x0000000000000003, 0xfffffa800761c6b0, 0xfffff803304187f0, 0xfffffa8011aa7870). A dump was saved in: C:\Windows\MEMORY.DMP. Report Id: 042813-33109-01.

Some logs are here: http://sdrv.ms/10LGQ4N

Please help

Your Windows crashes because of the DRIVER_POWER_STATE_FAILURE (9f) bugcheck. WinDbg tells me that the MS PPP Framing Driver (ndiswan.sys) causes the issue.

Which Wide Area Network do you use?