Message type: E = Error
Message class:  ACC_ROLES - Messages for Type Concept Financials 
Message number: 018
Message text: Role &1 requires an ABAP class (&2)
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The SAP error message ACC_ROLES018 indicates that a specific role requires an ABAP class that is not currently assigned or available. This error typically arises when you are trying to assign a role to a user or when you are performing a role-related action, and the system cannot find the required ABAP class.
Cause: Missing ABAP Class: The ABAP class specified in the error message is not available in the system. This could be due to the class not being created, being deleted, or being in a different transport request that has not been imported. Incorrect Role Configuration: The role may have been incorrectly configured to reference an ABAP class that does not exist or is not active. Transport Issues: If the role was transported from another system, the ABAP class may not have been included in the transport request or may not have been imported correctly.
Solution: Check for the ABAP Class: Go to transaction SE80
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