These error codes usually appear when there are problems applying a system update to the console.
To fix these errors you will have to do an offline system update using an NTFS-formatted USB stick with at least 6 GB of space.
The steps you must follow are the following:
- Download the OSU1 file to your computer and unzip it.
- Copy the $ SystemUpdate file that you will find among those extracted from the zip in the root directory of the pendrive (it is important that the USB memory is empty, that there are no other files or folders).
- Turn off the console and connect the pendrive with the previously copied file to a free USB port.
- Turn it on again by holding down the link and eject buttons, and at the same time press the Xbox button (for the One S All-Digital Edition version, press and hold the link button and then press the Xbox button).
- Press and hold the link and eject buttons until you hear two power-on tones.
- After the second release the buttons and the console will open the startup troubleshooter.
- Select the option System update offline using the Xbox controller and start the update process.
After a few minutes the console will restart and return to the home screen. If everything went well, the E101 error should be gone.