3498818 - Error: Phase CREATE_UPGEVAL fails with ILLEGAL_FILENAME at the end of the upgrade

During the upgrade of a system or conversion to S/4HANA, the final phase CREATE_UPGEVAL throws the following error when saving the UPGANA.XML file:

PHASE_CREATE_UPGEVAL.SAV

1 ETQ233 Calling function module "SUBST_SLANA_STORE" by RFC
2 ETQ373 parameter "INSTNR" = "0011111111"
2 ETQ373 parameter "SID" = "SAP"
2 ETQ373 parameter "EVALTYPE" = "SUMO"
2 ETQ373 parameter "STARTDATE" = "20240702161832"
2 ETQ373 parameter "ENDDATE" = "20240708133627"
2 ETQ373 parameter "FILENAME" = "/usr/sap/SUM/abap/tmp/UPGANA.XML"
1EETQ235 Call of function module "SUBST_SLANA_STORE" by RFC failed (error-status "5")
2EETQ360 RFC of "SUBST_SLANA_STORE" failed:
2EETQ361 code/exception  : 5
2EETQ362 key             : ILLEGAL_FILENAME
2EETQ399  Number:000
4 ETQ010 Date & Time: 20240708133648.607
1EETQ399 Last generated error message is: RFC system Q00 nr 01 function 'SUBST_SLANA_STORE'
1EETQ399XRFC failed with code 5 key ILLEGAL_FILENAME:
1EETQ399X Number:000
1EETQ204 Upgrade phase "CREATE_UPGEVAL" terminated with severe errors ("20240708133648")

• SAP S/4HANA
• SAP ERP 6.0
• SAP NetWeaver 7.x

KBA , BC-UPG-TLS-TLA , Upgrade tools for ABAP , Problem