Reading from harddisk and Writing as VMDK using VDDK

Hi,

I wrote a program to read from the hard disk(raw read) and write to a VIXDISKLIB_DISK_MONOLITHIC_SPARSE file. While writing I calculated the StartSector (2nd parameter to VixDiskLib_Write) like this

1. Start Sector - "Actual Disk Offset / 512"

2. Number of sectors - "no of blocks to write * 4096" (each block is of size 2MB).

The file gets created and gets attached - but the data is raw.

Is the way in which I write the data is correct? How can I verify whether each block I write is correct? The system I am testing this is Windows 7 & Visual Studio 2008. Help is really appericiated.

Thanks,

./Siva.