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Access the Inventory module.
Click Inventory Adjustment.
Specify the Inventory Type.
Optional: Enter in the Item Code or click on the ellipsis to return a list of items for that Inventory Type.
Select an Inventory Location.
Specify an As of Date. This will return inventory as of that date and the adjustment you enter will occur for this date.
Click Retrieve.
Click the Item that you wish to adjust.
Click Adjust Inventory.
Locate the specific line of Inventory for this Item that you wish to adjust.
Click in the Adjustment Qty or Adjustment Pack column.
Specify either a Quantity or Pack value. It should auto calculate the other.
A positive number will add inventory, a negative number will subtract inventory.
Select an Adjustment Code on the line.
Specify an Adjustment Date.
Select a Post to Period option.
Click Save.
Click Close.
Repeat step #8 to #17 for the next item you wish to adjust.
Click Save and Close.
You have now adjusted inventory item as of a date.