Question:

What is the difference between dunning clerk and accounting clerk?

Answer:

This is usually referred to depict the responsibility. 

Accounting clerk you will find in G/L account master in FS00 who is assigned responsibility to maintain and clear this account, he/she has track every movement in the account. 

Dunning clerk is the clerk who is responsible to dun the particular customer and send notices. 

Dunning Clerk is responsible for running the process of Dunning. 

The name of Dunning Clerk is printed on Dunning Notice whereas the Accounting Clerk is responsible for running the Automatic payment run program and his name can be printed in foot notes of Payment cheques etc.
 

When Can They Be The Same

There can be scenario when both dunning and accounting clerk are same.

In some organization, the Accounting Clerk and Dunning Clerk may be same but in system, there must be two separate persons but you can assign same IDs and name.
 

Configuration

You can configure the Dunning clerk in the same place where you had configured the Accounting Clerk.

Both the field names are BUSAB, but Accounting Clerk is maintained in table KNB1 and the Dunning Clerk from KNB5. 

Master table for the both is T001S.

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