Factory reset gone wrong

If your model is from 2011 or later, then you should be able to do this:

Internet/Network Recovery of El Capitan or Later on a Clean Disk

     If possible back up your files before proceeding.

1. Restart the computer. Immediately, at or before the chime, hold down the (Command-Option-Shift-R) keys until a globe appears.
2. The Utility Menu will appear in from 5-20 minutes. Be patient.
3. Select Disk Utility and click on the Continue button.
4. When Disk Utility loads select the target drive (out-dented entry w/type and size) from the side list.
5. Click on the Erase button in Disk Utility's toolbar. A panel will drop down.
6. Set the partition scheme to GUID.
7. Set the Format type to APFS (SSDs, only if installing Mojave or Catalina ) or Mac OS Extended, (Journaled.)
8. Click on the Apply button, then click on the Done button when it activates.
9. Quit Disk Utility and return to the Utility Menu.
10. Select Install OS X and click on the Continue button.

Are you downloading by browser? If so, then use only Safari. Initially, it sounded like the disk was going bad. Did you have any problem reformatting the disk? What version of OS X do you need to install? If you're unsure, then tell us what exact model you have. To find the complete model information select About This Mac from the Apple menu. You can create a snapshot of the dialog as follows:

How to take a screenshot on your Mac

Capture, Save or Record Screenshots in Mac OS X - Help Desk Geek

OS X Screen Capture Shortcuts

(⌘⬆︎3) Command-Shift-3 Capture the screen to a file

(⌘⬆︎⌃3) Command-Shift-Control-3 Capture the screen to the Clipboard

(⌘⬆︎4) Command-Shift-4 Capture a selection to a file

(⌘⬆︎⌃4) Command-Shift-Control-4 Capture a selection to the Clipboard

(⌘⬆︎5) Command-Shift-5 Invoke new screen grabber

You can then post the image in the forum's message editor.

Saved my bacon! Thanks!

Tell us all the information. Where or when did you get that error? What were you doing before the error appeared?