I'm trying to overwrite directly to a file on a Compress NTFS file system.

It seems that Vista onwards Microsoft does not all to directly write to a cluster. http://support.microsoft.com/kb/942448
Even if I'm an Admin WriteFile to a cluster always returns with 0x5 (Permission denied). BTW, I'm using DeviceIoControl (FSCTL_GET_RETRIEVAL_POINTERS) method to get the file cluster list. And then open Volume with CreateFile method.

But it seems that HDDScan can erase any sector on a Compress NTFS file system. I was wondering if someone could help me on how to resolve this issue. Any sample code or list of Window API which can allow writing to a cluster.

Last question, how can we convert a cluster number to LBA number and how we can get physical device info a file?

Many thanks in advance.