You needs to make tax only credits in GP
Microsoft Dynamics GP 2010
- In Avatax Config page, Tax Calculation tab, make sure that AvaTax Integration for Account Receivables Entry and Tax Amount Adjustment functionality via Receivables Transaction Entry are both checked.
- You'll need to be logged in as SA and everyone must be logged out of GP to make this change.
- Then in the credit memo, after you have entered customer, click on Additional and then AVA RM override.
- Fill in the necessary info to complete process.
- Ensure that the tax schedule is still listed as AVATAX, and enter a tax amount
- Hit OK
- On the popup window, enter the tax schedule as AVATAX again, and enter the tax amount and hit OK/save
- Your tax only credit should be on the admin console