Hi!
Please perform the following steps in exactly this order. If they don't work, start over from the beginning and make sure you follow each one exactly. If that still doesn't work, contact us via Chat.
1) Format a flash drive GUID partition scheme and Mac OS Extended format. Name it Firmware
2) Drag the attached SCBO file to your Desktop.
3) Open Terminal.
4) Paste the following command into the terminal window and press enter:
cp ~/Desktop/SCBO /Volumes/Firmware/.SCBO
You should get a new line, no errors.
5) Paste the following command into the terminal window and press enter:
cp ~/Desktop/SCBO /Volumes/Firmware/._SCBO
You should get a new line, no errors.
6) Eject the flash drive.
7) Turn off the customer's computer.
8) Insert the flash drive.
9) Turn on the customer's computer and immediately hold down the Option key.
You should see the lock symbol for a second and then it will restart to the Startup Manager.