2228162 - SQL0970N The system attempted to write to a read-only file

The SAP system won't start due to R3trans failing with SQL0970N error.

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4 ETW000 [ dev trc,00000] DB2 client driver version '10.05.0007'
4 ETW000 [ dev trc,00000] Running with CLI driver.
4 ETW000 [ dev trc,00000] *** ERROR in DB6Connect[D:/depot/bas/742_REL/src/dbs/db6/dbdb6.c, 1981] CON = 0 (BEGIN)
4 ETW000 [ dev trc,00000] &+ DbSlConnectDB6( SQLConnect ): [IBM][CLI Driver] SQL0970N The system attempted to write to a read-only file. SQLS
4 ETW000 [ dev trc,00000] &+ TATE=55009
4 ETW000 [ dev trc,00000] &+
4 ETW000 [ dev trc,00000] &+
4 ETW000 [ dev trc,00000] &+
4 ETW000 [ dev trc,00000] *** ERROR in DB6Connect[D:/depot/bas/742_REL/src/dbs/db6/dbdb6.c, 1981] (END)
4 ETW000 [dbdb6.c ,00000] *** ERROR => DbSlConnect to 'SAP' as 'sapsap' failed
2EETW169 no connect possible: "DBMS = DB6 --- DB2DBDFT = 'SAP'"
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Db2 commands may report the same.
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E:\db2\db2sap\db2_software\BIN>  db2 connect to sap user sapsap
Enter current password for sapsap:
SQL0970N  The system attempted to write to a read only file.  SQLSTATE=55009
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• Netweaver AS ABAP any release
• DB2 LUW (DB6) any release

SQL0970N , -970 , DIA8701C , -2079391743 , KBA , BC-DB-DB6 , DB2 Universal Database for Unix / NT , Problem