Sorry for confusion. The PC is up and running, but all my data is still on an external drive where I can't get at it. I tried the services of Iyogi - they could't work out why the windows restore would not restore a DSG file!

So i'm no further forward. I've tried MagicISO and WinImage both to no avail. It can't be that difficult, sadly I don't know anyone with a Mac - I'm nead Bedford if anyone is close?

How big is the dmg file? How sensitive is the data?

Right - got it. Sorry for the 'confusion' on my part - I assumed 'system now restored' meant back to where you wanted it.

Have you been in touch with Seagate Tech Support? There is a warranty.

My La Cie USB external came with two folders on it, one for Mac and one for Windows. I was asked to install the appropriate programme. I chose not to, and used MS Backup instead. My point being that I would have expected - somewhere - a choice to be offered to you between a Mac b/up and a Windows?

I'm fascinated - is this yet another Vista compability problem?

Did you (from the Seagate site)

1. Connect your FreeAgent Desktop drive to your computer. System Tray Notifications identify the connection of the drive and the AutoPlay window opens.
2. Click Install FreeAgent Desktop Software. The Select Language window opens.
3. Select a Language (e.g., English) from the list provided.
4. From the next screen, click Install Software.
   Note to Windows Vista Users: A User Account Control window opens asking for your permission to continue. Click Continue.
   The InstallShield Wizard prepares the Drive Manager Setup. The Welcome window opens.
5. Click Next. The License Agreement window opens.
6. Select a translated, End User License Agreement (e.g., United States) and click on the Next button.
7. Click Yes to accept the terms of the License Agreement. The Choose Destination Location window opens.
8. Accept the default destination folder or click Browse to select a different folder. Click Next. A Setup Status window keeps you informed as the installation proceeds.
9. When the installation is done, the InstallShield Wizard Complete window opens. Decide whether to restart your computer and complete the installation now and click Finish.
10. At this point, the Drive Manager application opens. Click on the "X" to close the program.
11. Click on the Exit button to close the installer. ??????

Is there no option in 'Drive Manager application' to restore?

Thanks BOAC.

When my desktop crashed i was essentially given two options, to back up and reformat, or reformat. I chose the former. I plugged in the new external hard drive and it backed up. There were no options and my PC was in no state to select anything. I just assumed, maybe incorrectly, that the back up would be readable to Vista.

I think Seagate tech support is my next call in the morning. The likes of PC World, I-yogi etc have no idea. The data is not sensitive, but it is important, i'd gladly pay anybody's fee but having spoken to around 30 people now i'm starting to think a solution is not available. If this file were full of something say the police were interested in i'm sure they would find a way, any coppers out there?

I managed to open a DMG in Fedora/RedHat/Linux, maybe at a last attempt you could try that.

However, i have used the following tool

http://www.acutesystems.com/scrtm.htm

Its called transmac, there is a 30day demo, so you can see if it works, and its about £30.

From a little searching on the internet, the best tools i could see are.

UltraISO
MagicISO

There are a few tools that convert DMG to iso's but they seem to be unreliable.

I have used TransMac, i know it works, so i would give it a shot first.

You say you have used one of the tools i listed, so i am guessing the other is no good. You can download a copy of VMWARE Player and Fedora for free, Linux and MAC/BSD use a similar file system.

I always try WINRAR from RARLABS to extract anything and everything, have you tried that?

Having lost my partition recently, i have been trying some data recovery tools, they seem to find loads, stuff i deleted a fair while back and a few os installs ago, i use pretty much all my hdd, so it didnt find too much as i am always going over the hdd. worth a shot.

Have a go at DMG to iso too, its free, but i am lead to belive its pretty hard to use?

Last thing i could find is

http://www.mediafour.com/products/macdrive6/

its supposed to ipen DMG, well be able to mount.

Well chaps thanks for all your ideas, in the end nothing was able to extract these files that I could find. So i've taken the step of having the hard drive recovered, that brings it's own challenges but at least I'll have the data. Cheers again.