Support 101 - Living with UEFI

Having been upgrading customer machines to W8.1, the new Acer TC-105 I'd supplied new was the first I've had with the new UEFI replacement BIOS. It was supplied pre-installed with W8 which was upgraded to 8.1 before any use, but I'm not quite sure now when the blank disks supplied with the machine were populated. That is something else to check before  it gets returned.

It had been running fine for 3 months, but last week rather than booting up it failed with the blue screen 0xc0000034 error with the only option to switch to UEFI.

After a little digging found out how to disable secure boot in UEFI so could actually boot from the disk. I has to switch off 'secure boot', enable the legacy scanning and ensure the DVD was accessed first. Acer Help Desk Guide almost gets there, but I had to go back in and move the DVD above Windows Boot Manager on the Boot tab. Also on the boot tab is a switch to enable the boot select menu using F12 instead of Del.

None of the none distructive automatic recovery tools worked so I ended up in the recovery console. Initial serches all advised using 'bootrec /rebuildbcd' which found the C:windows installation but failed to update with a 'The requested system device can not be found'. To cut an anoyingly long story short, the magic key is not bootrec, but bcdboot, and eventually a post to the Microsoft Community Forums returned 'Fix the boot configuration' confirmed that, although I think during the may cycles around I did also run chkdsk as documented on the additional fixes link on that page. In my wooly brain I seem to recall it did find a fault as I had to run again with the /F switch, so perhaps that should always be run before bcdboot.