Error Code 560 in Vantage 6

Have any of you ever received an error code 560 while running MRP. It's happening for us during the deletion of
unfirm jobs. We made changes yesterday to our Work Center schedules,
which is what Epicor says causes the problem. I guess I don't
understand how this relates to the unfirm jobs nor how to fix it. They
say it will work itself out. We are in Vantage 6.0 and on Progress
9.1D. We run MRP every night. We normally REGEN and we don't run

Any thoughts?


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