You are preparing to program a replacement system board, but the "system is booting in mpm mode" message is not displayed. what must you do?

The bios is not setup properly for the system, as such the OS is not loaded properly. It is basically on factory mode state of unit testing, if the unit is in warranty have the vendor fix this as they have to deactivate the MPM or manufacturing programming mode or from your end make sure that the disk which contains the OS is properly loading.

Do nothing. If your computer has Windows 7/8/10 and you are changing the motherboard, it is possible that the operating system will boot successfully without extra efforts after replacing hardware. It takes a few steps to do, but it is possible to change the motherboard without reinstalling Windows. E.g. by changing the registry values and or using backup software like AOMEI.

Explanation:

If the message "system is booting in mpm mode" message is not displayed, it means it isn't in factory mode. MPM mode refers to manufacturing programming mode and it is used for unit testing.

storage maybe?

are there options?

make sure each item is its own paragraph.