You can set up a default VAT product posting group code for each general product posting group code and have the program insert the VAT product posting group code along with the general product posting group code. If you decide not to do this, then you must assign codes to your item and resource accounts.
Open the Item Card window or the Resource Card window.
Browse to the card on which you will enter a VAT product posting group code, and click the Invoicing tab.
In the VAT Prod. Posting Group field, click the AssistButton to see the VAT Product Posting Groups window. Select the line with the desired posting group, and then click OK to copy the code to the card.
Repeat the procedure for each item or resource account.
Assigning VAT Business Posting Groups to Customer and Vendor Accounts
Assigning VAT Posting Groups to G/L Accounts