Reference Account Group for One-Time Accounts
Description
For master data of a one-time account, a reference account group can now be specified under "Control" in the "General data" part (on the debit side or on the credit side, depending on the account type of the one-time account). The fields of the one-time screen are controlled via this when posting to the one-time account. It is thus possible to define fields as required-entry fields or to hide them (this is necessary, for example, for the tax number in Spain). For the document change or document display, the field control is carried out similarly, where the changeability of a field is additionally determined by the document change rules.
If you do not specify a reference account group for the master data of a one-time account, all fields of the one-time screen are ready for input as before when entering a document.
As a reference account group, you can use an already existing account group, providing you reach the required control or define one or several new ones you use particularly as reference account groups.
Change system parameters in customizing
You define account groups in the "Accounts Receivable and Accounts Payable" Implementation Guide.
Deselect the "General data" field status and choose the required control for the fields of the one-time screen. For an account group you particularly use as a reference account group, the general specifications on this account group as well as the field status of fields that do not exist on the one-time screen are unimportant.
For more information, refer to the Implementation Guide chapters 
"Define account groups for customers" and
"Define account groups for vendors" .