3812037 - Where can I find a list of status codes (Invoice)?

When I look at my invoce approvals there are various codes that I don't understand.
Where can I find out what they mean?

Invoice > Invoice Settings

Concur Expense all versions ; Concur Invoice all versions

I would like to understand what codes like R_NOTF mean , KBA , CON-REQ-REQ , Request , CON-EXP-EXP , Expenses , Problem

This is a preview of a SAP Knowledge Base Article. Click more to access the full version on SAP for Me (Login required).

Visit SAP Support Portal's SAP Notes and KBA Search.