Group: Awaiting Activation
1. tinker with the "Rescue environment boot menu option ...
no, have been using it same way since Macrium was installed
2. any chance a BIOS update might have been applied ...
If so I didn't know it, and have not kept a record of the bios version. There is such an application, it's from HP and it checks for updates, don't think it ran that day.
3. are you sure you'd remember anything else ...
Not sure, as in bet the farm on it, but I thought about it quite a bit at the time and didn't remember anything that seemed relevant.
There is one thing, when I restarted after the Macrium update, I had the xp drive unplugged. Wouldn't boot after that, didn't show in the BIOS
4. Last paragraph above ...
I didn't specifically enable the Compatibility Support Module, but it may have been enabled already. Also didn't turn it off.
After much wrangling to get the correct drivers for win xp, all I had to do was select the correct HDD, and the OS on it would boot.
And thanks for the help, hope we can fix this.