My windows device is having a lot of issues. It's infinitely booting, having device i/o errors and failing most operations. I am unable to boot into Windows. I have a Dell optiplex 790.
Start the computer and when the Windows logo appears, press and hold the power button until the computer shuts down. Do this twice and the third time the computer should boot into the recovery environment.
Ben
If the hardware itself isn't malfunctioning, I recommend imaging the hard drive first. A popular tool is Macrium Reflect Free. (I've used Acronis True Image, but it's not free.)
You'll need a USB flash drive (thumb drive), and an external USB hard drive with enough free space to accept the image of the hard drive of the Optiplex. (Just the contents, not necessarily the full size of the drive.)
Install Macrium on another PC, and use it to create a bootable USB rescue drive.
Connect the external USB drive and the thumb drive to the Optiplex.
Boot the Optiplex from the thumb drive. (I'm not sure, but it may be the F12 hotkey.)
Backup the Optiplex onto the external USB drive.
What you'll get is an "image" of the Optiplex's drive. You can use Macrium to extract data from that image if necessary.
Best of luck. If this is too much for you, get human help. If you take the PC to the Best Buy Geek Squad, you may have to say goodbye to your data. (They may get the PC working again, but they may not save the data.)
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