You can't format a partition before it has been set up.
I am quite sure that the quote has been cut from the context. The other thread probably talked about a read error on an existing partition.
You can't low level format IDE HDD.
But you can let HDToolbox send the command to the drive. Different drives behave differently when receiving this command. I have had drives with read errors in cylinder 0 which could be partitioned after a LLF attempt. The command obviously cleared the internal bad block list of the drive allowing it to use replacement sectors for cylinder 0. (One could clearly hear the head move to the end of the disk and back when accessing the RDB). Of course the drive didn't become better by this. The read errors only reappeared at another place of the disk. I had to trash it anyway.
error 21
If you did everything right, error 21 usually means that the drive is dead. But if you are unsure whether you did everything right you can still search your mistake. For example having two masters or two slaves on the same IDE cable can cause read errors. Or a weak or overloaded power supply. Or a bad or improperly connected cable.
Bye,
Thomas
