After new Win 7 install - msg: Operating System Not Found

Do you have the latest BIOS version?

Have you tried a DVD install?

Hi gregrocker, Yup to all of the above. Down level BIOS was my first thought so flashed the
latest I could find (V1.18).
Tried numerous different DVD installs. I'd need a pretty big matrix to cover all options:
DVD, USB, Formatted HDD with various tools both bootable from emac machine and external to MSI machine via USB to SATA cable, Pre-partitioned with various bootable tools, Partitioned during install. Removing USB stick on first reboot etc etc. I have tried everything mentioned in the thread and every other option I can think of. Also a variety of bootable MBR tools as well as bootrec and bcdedit. Different BIOS settings. A Mixture of all options. 5 days worth of everything I can think of and everyone on the thread. Still comes down to Operating System not found on the emacs machine but boots on the msi machine.
Starting to think strange things now. Could eMachines have altered the BIOS to look for something strange??
The V1.18 I flashed was from their website. But how would that explain my MSI disk booting no probs when
in the emachines hardware..

You've tried other HD's booting in the eMachine? You can adapt another Win7 to boot using Paragon Adaptive Restore CD - SkyDrive

Gregrocker, cheers. The beauty of the cloud eh? Just had a quick look. Does this mean I can store a bootable image from my working system (MSI) through skydrive then network install on emachine? Sorry to bring my Unix roots up, but like NIM on AIX..

The file size limit on Skydrive is 2gb I believe. You can buy extra space for cheap.

I would keep trying different HD's until you find one that agrees with that eMachine. There is something very strange about your issue. I've not seen one like it before.