I can't virtualize Windows 7

Hi

I have a laptop with Windows 7/server2012 (180 days trial) dual boot with a HDD of 500 GB with the following partitions

C: windows 7 100 GB

D: WS 2012 100 GB

E: STORAGE 300 GB

I used the disk2vhd to convert the 3 partitions into 1 VHD, but when I create a new VM on hyper-v to try to run this vhd, I don't get anything, just a black screen with a flickering white line at the p left side of the VM screen.

Next try I made was editing the boot manager so the laptop boots only with windows 7, I used the disk2vhd again to create the vhd and the result was the same.

Is there something I'm missing? do I need to erase the D partition with WS 2012 so I can convert the disk to vhd and virtualize it succesfully?

I hope anyone of you can help me

thanks!