THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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What's on the screen?
To do 
How do I create a new invoice line item?
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How do I update an invoice line item?
Not all the fields on the invoice item line can be updated. For example Taxable Flag and Inventory Item cannot be updated. If these fields need to be amended then the invoice item will need to be removed and then re-created.
Example: To update an invoice line item
- Select the 'Items' sub menu for the invoice
- Any existing line items will be displayed in the 'Items' box
- Amend the details in the line item that needs to be updated (eg Quantity, Invoice Item Type, Product Id, Description, Override GL Account, Unit Price)
- Press the 'Update' button displayed at the end of the line item that has been updated
How do I delete an invoice item?
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Example: To delete an invoice line item
- Select the 'Items' sub menu for the invoice
- Any existing line items will be displayed in the 'Items' box
- Press the 'Remove' button displayed at the end of the line item that needs to be deleted