after a failed windows 8.1 update, computer will not boot.it saysautomatic repair then it stop and give the options to restore or cancel and restore does nothing, just the windows logo for hours and during this time it just keeps getting hotter and hotter.

No success booting to safe mode? Rather than trying to repair, have you attempted a clean install?

cant get windows to boot from instalation disk .neither usb drive

shift and f8 combination not working to get into safe mode

There's something else going on here then because no matter what condition the operating system on the hard drive is, you should always be able to boot from bootable media.

If you can't boot from a windows DVD then your BIOS settings are not configured to boot to other devices prior to the hard drive or the device is bad or the media is bad.

so........ you have any suggestions?
whats my next step?

I tried windows boot genius as was suggested at the link recommended but no luck. cant get laptop into boot mode

Did you get its free version? if you paid for it, you may contact its customer service.

If you cannot get as far as to boot from another media, then it means that the bios boot sequence has been altered. Microsoft has a long history of making tweaks to the bios firmware as part of an intermediate step in the installation (or update, I guess). Basically, if something did not go right during the installation, your computer is stuck in a state where all the bios tries to do is continue the installation, ignoring any other booting rules (such as booting from a rescue media (USB / CD / DVD)).

What you will need to do is jump the cmos jumper to do a factory reset of your bios. Here are some basic instructions, but you will want to find instructions specific to your computer hardware (specifically, the motherboard). Doing this will certainly make it possible to boot into a rescue media and install / re-install whatever you want. I've had that exact same problem before (it was back in the days of Win2000, but it seems old habits die hard at Microsoft).

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.