Cause:
System will not allow the user to save Purchase Order with new item series if the new item series is not mapped in item account determination with the account code and cost center code. System will show the following error ‘INVALID ITEM TYPE’ or ‘Invalid Account Code!’.
Solutions:
User should map the new item series with the Purchase order account code in item account determination. For Item Account Determination master, go to Finance->Finance Setup-> Masters->Item Account Determination.