Error: The following UOM codes are unavailable for use in the Unit Configurations

In certain cases, the following error will appear when saving an item:

The following UOM codes are unavailable for use in the Unit Configurations: {unit(s) of measure}. Please add them as Input UOMs or reconfigure the involved unit configurations.

Go to Item Aspects > Unit Configurations. You should see one or more unit configurations present with the unit(s) of measure in the error message being used, while not being linked to the item as either base or input unit of measure.

The easiest way to fix this is to add the unit(s) of measure to Units of Measure > Input Units of Measure.

Changing the base unit of measure is another option, so long as no transactions exist for the item.