Address number
must be removed after the upgrade to 46C has taken place 
Use
As from Release 4.6C, GUIDs are used for cross-system identification of business partner addresses. This means that existing records in table ADRV (where-used list for addresses) for relationship addresses have to be amended in that the address number stored in field ADRV-APPL_KEY is removed.
To do so, start program BUPRADRVPCHANGE after the upgrade.