Are you seeing messages such as:
Boot failure: a proper digital signature was not found. One of the files on the selected boot devise was rejected by the secure boot feature
Or just a black screen with a blinking cursor?
This is probably due to the "Secure Boot" feature currently on all new Windows 8/8.1/10 computers. Secure Boot is a new feature that improves the security of Windows. The intention of Secure Boot isn’t to “lock out” other bootable devices, but this is just an unintended consequence of the feature.
To get the FixMeStick working, you will have to disable Secure Boot.
Note: FixMeStick usually can still boot up with no problems on some Windows 8/8.1/10 computers with Secure Boot enabled.
Here are instructions for disabling Secure Boot on Windows 10:
1. Insert your FixMeStick into your PC.
2. Click on the start menu and select "Settings."
3. Then select "Update & security."
4. Select "Recovery" and then click on "Restart now" under Advanced start-up.
5. A new menu will appear. Click "Troubleshoot." Then click "Advanced Options."
6. Click "UEFI Firmware Settings."
7. Click the "Restart" button and wait for the computer to successfully restart.
8. Your UEFI Firmware settings will appear. Try to locate the "Secure Boot" option using the arrow keys on your keyboard. Here is an example image:
Not all BIOS menus are the same, but these options typically appear in the "Security" menu. These options might also appear in a different menu, so you might have to search around. Once you see a secure boot option, disable it by highlighting it with the arrow keys and then pressing enter. Once it is disabled, restart your computer by pressing F10 (which saves your changes and exits the BIOS). If F10 does not work, find your way to "Exit" and then always select the "Exit and Save Changes" option.
9. Start Windows and double-click on FixMeStick.exe. The FixMeStick should now launch normally.