Thanks for the info.
noahhu wrote:I was tring to mark bad sectors of my portable disk using the MHDD.
With respect, are you sure that you've done enough research and have enough experience for this to be an appropriate plan? Depending on the exact symptoms, the SMART data, the reported Windows error messages, and your expectations regarding the data on the disk etc., this may not be sensible... Do you have backups of the data which is on this disk?
noahhu wrote:An error was showing to suggest a 64bit version of the software was required when I try to run it in the CMD console of win7.
That is an erroneous suggestion from Win7, caused by you trying to do something that is not intended to work anyway i.e. trying to run MHDD from the Win7 command prompt (which is not DOS).
noahhu wrote:I understand that the MHDD will works smoothly in a pure DOS environment. But I don't have any console except for the CMD console of the win7 on my computer.
If you run MHDD from a bootable DOS CD (or USB), which can be downloaded, then it doesn't matter what OS is installed on your PC.

As I said before - I politely suggest you take a step back, and re-consider your plan. If you still want to go ahead, and you agree to accept the consequences, make sure you read
all the MHDD docs, including the "important information" warnings and recommendations.