I recently formatted my C drive and reinstalled windows XP. No problems - all works fine - apart that is from an external Maxtor One Touch hard drive that was connected to the PC by Firewire. This drive, with two particitons, had worked fine but following the XP reinstall the PC no longer recognised it, nor did any other PC recognise it. Partition Manager eventually allowed me to see the Maxtor. But although it showed the two partitions it reported that neither was formatted.

Any suggestions for what has happened here. I could understand it if the drive had been inadvertantly reformatted during the reinstall but clearly, since the drive is showing unformatted, that is not the case. I can't see how I could have 'unformatted' the drive and I am assuming that the data is still there but not being recognised for some reason.

I could of course simply reformat and start again, but I have some data on the disk that I would like to recover if possible All suggestions welcome.

This usually occurs for a couple of reasons.

The disk was formatted as a “Dynamic Disk”. A Dynamic Disk is an advanced volume structure in Windows 5.x (2000, XP and 2003) that works without using partition tables. But therein lays the problem. Dynamic Disks cannot be moved between one volume and another.
Unfortunately, when entering the Disk Management MMC snap-in for the first time, the logical disk manager automatically prompt for the initialization (serialization and partition table creation), volume creation (file system creation), and facility to convert the volume to a dynamic disk. Many people accidentally go through with this, not really realizing the consequence. There are ways to move dynamic volumes from one installation to another, but not without preparation.

Or, for some reason, Windows no longer recognises the partition table. This can happen because the file system was improperly dismounted (common for USB mass storage devices), it was incorrectly initialized by Windows, was incorrectly serialized on creation, or tens of other possibilities.

You could try a few tools, like Partition Magic, to see if you can repair the partition table, or convert it to something very basic, like FAT32. Beyond that, the outlook isn’t great.

On a personal note, I once lost 160GB of data this way. I was never able to recover it. Good luck :-\

You can try this it's a beginers recovery tool and it's free maybe you can recover your files before reformating: http://www.pcinspector.de/download.a...#file_recovery