2350473 - During system copy, R3load fails with DbSlErrorMsg rc = 20

While running a system copy procedure with the user <sid>adm, during the export with SWPM, in the phase step "Prepare to export ABAP", the following error occurs:

(DB) ERROR: DbSlControl(DBSL_CMD_IMP_FUNS_SET) rc = 20
(DB) ERROR: DbSlErrorMsg rc = 20".

Testing R3load.exe -testconnect results:

C:\Users\sidadm>r3load -testconnect SID
r3load: START OF LOG: 20160802153306
(BLD) INFO: sccsid "@(#) $Id: //bas/745_STACK/src/R3ld/R3load/R3ldmain.c#4 $ SAP
"
(BLD) INFO: kernel release 745 [UNICODE]
(BLD) INFO: data format 1.8
(BLD) INFO: patch number 100
(BLD) INFO: compiled on "Feb 26 2016 14:35:52"
(PRC) INFO: working directory "C:\Users\sidadm"
(PRC) INFO: called "r3load -testconnect SID"
(PRC) INFO: process id 5660
(LOG) INFO: log level: 1
(LOG) INFO: log format: classic
(DB) ERROR: DbSlControl(DBSL_CMD_IMP_FUNS_SET) rc = 20
(DB) ERROR: DbSlErrorMsg rc = 20

r3load: job finished with 1 error(s)
r3load: END OF LOG: 20160802153306

g the connection to the database with R3trans -d results in the following error:

2EETW169 no connect possible: "connect failed with DBLI_RC_LOAD_LIB_FAILED."
r3trans finished (0012).

And in the trans.log file you can find the following entries:

4 ETW000  [     dev trc,00000]  Tue Aug 02 08:19:35 2016
4 ETW000  [dbcon.c     ,00000]  *** ERROR => Invalid profile parameter dbms/type (or environment variable dbms_type) = <undef>, cannot load DB library
2EETW169 no connect possible: "connect failed with DBLI_RC_LOAD_LIB_FAILED."

• SAP NetWeaver based systems with ABAP Stack or Dual-Stack;
• MS SQL Server 2008 and higher;

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