External HD freezes after formatting failed

I have a WD 250Gb external hard drive that I tried to format and use as a backup. I unchecked the tick box that said 'quick format' and left it to format. It took over and hour before i got the message along the lines of 'formatting failed'. Now when I plug it into my PC I can't access it and it freezes as it constantly tries to find it. The external HD is working, and the little white light is flashing.
In Computer Manager, the disk is showing up in RAW file system, rather than NTFS, and says it's healthy primary partition. I've tried to do a quick format from there, but that fails too.
Any advice please?

Additional info - when I unplug the HD now, i get the message 'device inaccessible, parameters incorrect'.

Hi dazzler,

Try this to zero-fill and initialise your external HDD to the factory condition and then format.

1. Download and run Windows Executable (works without installation) HDD LLF Low Level Format Tool. HDDGURU: HDD LLF Low Level Format Tool . Do a lowlevel format..

2. Once the Lowlevel format is completed - it may take quite sometime to zero-fill all the sectors but you can watch the progress - download and do a regular format with HP USB Disk Storage Format Tool Download HP USB Disk Storage Format Tool 2.2.3 Free - Windows-based Format Utility for HP Drive Key or DiskOnKey USB Device - Softpedia

Again this is a Windows executable. Right click and Run as Administrator.

Thanks Jumanji - I'll give it a go and let you know the outcome.

I'm afraid I've already hit a problem Jumanji - when I started to run the low level format the software stopped responding and finally came back with the message ' unable to lock device. Make sure you do not have any open files on this device and try again'.
Of course, I don't have any files open. Blimey, Windows really did mess it up, didn't it?

Hi Jumanji - no joy I'm afraid. I've tried doing as you say on a second PC (which just locks up the whole PC until you disconnect the problem HD), and also on a laptop, which hangs once you press the 'format this device' button on the HDD Low Level Format tool and doesn't get past the 'locking device' bit.
I'm afraid I'm all out of ideas.

Jumanji - I didn't have enough patience - I left it for about half an hour and it did the job at last. The odd thing is that i could still access all the files on the disk, so it didn't really format it, just removed the partitions (I think). So I can currently see the drive on the laptop, but when i put it into the PC, it's not recognised. I'll get there in the end!
Thanks for your help Jumanji.

1.Do not shift your ext. drive from one machine to another machine. That can confuse the whole issue and you ( and me) will not know where exactly you are :). Stick to the machine on which you had the problem and try to fix it.

2. You had no intention of recovering any data and your problem was you are unable to format the drive. So the solution suggested was fully geared to achieving that without touching upon the data recovery aspect. Right?

3. In the lowlevel format tool you had perhaps checked "Perform quick wipe (just remove partitions and MBR" and then hit FORMAT THIS DEVICE. But our intention is to cleanse the drive completely by zero-filling all sectors to initialise it to the factory condition. So uncheck it and format. Then it will zerofill.





4. If you find the drive locked message, close the tool, safely remove the external drive and plug it in again. Run the tool. If it still says it is locked then shut down your machine,unplug the drive, reboot, plugin the drive and run the tool.

5. After the zerofill, run the HP tool as an admnistrator to do a regular format.