Job Issues error:  Overflow in RoundNum stored procedure

The most common source of this problem is a stock item with a fictitious on-hand quantity.  Usually, the stock item(s) has a quantity on-hand which is beyond the ability of the system to handle and generally represents something that doesn't actually counted (for example, tap water).  Instead of a stock item with a fictitious on-hand quantity, you may consider using a Descriptor or simply a note/task against the routing sequence which describes how much of the consumable to use.

The error appears to go away after adjusting the on-hand quantity of the stock item to a more reasonable level.  Note:  Extreme on-hand quantities can also cause errors in the Inventory data views.

To quickly find stock items that have extreme on-hand quantities, you may open (Inventory > Stock Adjustments) and sort on the 'Qty OH' column.