SAP Message AD213 - Please choose name VARKEY for second key field

Diagnosis
You changed the system proposal for the fields of a physical pool, buta physical pool has a fixed structure.
A pool must have exactly two key fields with the namesTABNAME (for the name of the logical pooled table) and VARKEY (thekey fields of the logical pooled table are stored as a string here).

Procedure
Set the definition of the physical pool back to theproposed structure.