The easiest and best way to do this is by using the Item Master Utility and changing the 'Purchase' or 'Sales' flags from N to Y. Then hit Process worksheet!
If you are not able to do it through the Item Master Utility for some reason, these steps will allow you to manually update the items.
Navigate to Inventory>Item Master Data and bring up the item you would like to change
If the item does not have a Bill of Materials associated to it and is not a component of any other item, skip to step #8
- Right-click on the background and choose Bill of Materials
- Make a note of the components, quantities, etc on the BOM. (Tip: Take Screenshots of a specific window)
- Right-click and choose Remove to delete the BOM
- Open the Bill of Materials for any items that use this item as a component (Tip: Use the Inventory Item Trace report to easily find this information)
- Remove the item from all BOMs(Right-click on the row and choose Delete Row) and make a note of which BOMs used this item and the quantity so you can add them back later
- Go back to the Item Master Data and check/uncheck the Sales Item and Purchase Item boxes as needed
- If you did not adjust any BOMs, you are now finished. If you did adjust BOMs, continue to the next step.
- Right-click and choose Bill of Materials again
- Recreate the BOM from your notes/screenshot
- Re-add the item to all of the BOMs where it was previously used