I have a secondhand Advent PC with MS WinXP Pro (with 5GB HPA) and want to erase entire HDD. I Tried to use MHDD v4 to remove HPA and erase enite HDD. I used the HPA Persistent command and erase HDD but when rebooted PC Primary Master IDE not working with any HDD, also the HDD HPA did not get removed after power off.

I have tried many erasing software to disable HPA but to no success.

Does anybody know why this is? Or can point me in the right direction.

I was thinking maybe need some sort of hardware/password to do this.

You just need to read docs more carefully.

I've read the english DOCs several times already and still can't get rid of HPA. Evertime it seems to work until I reboot PC then the HDD goes back to the original state.

Does this HPA need specific/original hardware/software to be disabled and get rid of it?

I've also tried the diskkill program to destroy the HDD with the virus.

have you tried NHPA command?

When I said that people need to learn more them HD Repair, I'm not joking and I'm not trying to ofend I just say what I'm seeing here.
Is to hard to get help with the right question, it will be impossible with the wrong or confuse question.

1- HELP!!! Not detecting Primary Master IDE after using MHDD v4
MHDD do not recognize the hard disk when it is in PRIMARY IDE
SOLUTION - Conect the hard disk in secondary and put it master

2- If you have HPA problems - this is another question -
Look at http://www.t13.org and you will start to learn about ATA commands. ANd if you really read the MHDD docs you already saw this mentioned there.
HPA - HOST PROTECT AREA.
Also like Dmitry already wrote try the proper commnd then you will get the right action.
With the key F1 it is possible to see all MHDD commands and for what they are.

3- To fix a hard disk that gott boot virus ( a kind of virus that do not permit that we fomat or do a new partition ) you just need to erase the first 1024 sectors, but for prevention it will be nice if you erase the first 1.000.000 sectors. And to do this use the erase command.

4- The first action ( IMHO) when you are using the MHDD is to scan the hard disk with ERASE WAITS on.

starting for a:\mhdd.exe