Using ALL branch plant in P00071 for MRP set up does not work?

We are in 9.2 and setting up the MRP system to help with inventory ordering for equipment maintenance items. I read in the MRP set up documentation that a "generic" branch plant of ALL could be set up in lieu of individual branch plants. This does not seem to work. I can get information in P3411 for branch plants that have work day calendars set up for them specifically but I get Date Generate Failed if I try to process R3482 on a branch that does not have a specific calendar.

Any ideas would be greatly appreciated!

Thanks!

Angelina