Siebel Administration >  SBL-GEN-05043: The specified user does not have the proper privileges to connect to the name server.

SBL-GEN-05043: The specified user does not have the proper privileges to connect to the name server.

Description:

This error occurred with Siebel 15.x, Windows and Oracle 12c.
Siebel was not starting.

Siebel Server complained in Enterprise Logs that Gateway Server was not available.
The error message in Siebel Server in File Siebel.log was 

ObjMgrSessionLog Error 1 000000025c170f3c:0 2018-12-17 12:29:28 (physmod.cpp (6946)) SBL-DAT-00373: DataSource named gateway could not be found.  Check your configuration file.
ObjMgrLog Error 1 000000025c170f3c:0 2018-12-17 12:29:28 (sqlbcdef.cpp (3503)) SBL-DAT-00373: DataSource named  could not be found.  Check your configuration file.
ObjMgrSessionLog Error 1 000000025c170f3c:0 2018-12-17 12:29:31 (physmod.cpp (6946)) SBL-DAT-00373: DataSource named Bugs could not be found.  Check your configuration file.
ObjMgrLog Error 1 000000025c170f3c:0 2018-12-17 12:29:31 (sqlbcdef.cpp (3503)) SBL-DAT-00373: DataSource named  could not be found.  Check your configuration file.
ObjMgrSessionLog Error 1 000000025c170f3c:0 2018-12-17 12:29:31 (physmod.cpp (6946)) SBL-DAT-00373: DataSource named Bugs could not be found.  Check your configuration file.
ObjMgrLog Error 1 000000025c170f3c:0 2018-12-17 12:29:31 (sqlbcdef.cpp (3503)) SBL-DAT-00373: DataSource named  could not be found.  Check your configuration file.

So we checked Gatway Server. It was not possible to start Gateway server. We went to Gateway logs folder and opened file NameSrvr.log  . The error message there was 

DBCLog DBCLogError 1 00fba1195c05050c:0 2018-12-17 10:08:55 [tp][ODBC Oracle driver][Oracle]ORA-12505: TNS:listener does not currently know of SID given in connect descriptor

GenericLog GenericError 1 00fba1195c05050c:0 2018-12-17 10:08:55 (secmgr.cpp (2768) err=4597538 sys=0) SBL-SEC-10018: [tp][ODBC Oracle driver][Oracle]ORA-12505: TNS:listener does not currently know of SID given in connect descriptor

GenericLog GenericError 1 00fba1195c05050c:0 2018-12-17 10:08:55 (secmgr.cpp (2824) err=4597527 sys=0) SBL-SEC-10007: The username or password you have entered is not correct. Enter your username and password again.
GenericLog GenericError 1 00fba1195c05050c:0 2018-12-17 10:08:55 (client.cpp (395) err=4597527 sys=0) SBL-SEC-10007: The username or password you have entered is not correct. Enter your username and password again.
SisnTcpIp SisnSockError 1 00fba1195c05050c:0 2018-12-17 10:08:55   1072: [TCPIP-server] recv() failed for sd=-1 (err=10038 | Socket operation on non-socket (invalid socket handle).)
SisnTcpIp SisnSockError 1 00fba1195c05050c:0 2018-12-17 10:08:55   1072: [TCPIP-server] send() failed for sd=-1 (err=10038 | Socket operation on non-socket (invalid socket handle).)

Solution:
Oracle Support web said that one of the reasons for this error is that the ODBC connections had errors.
We went to the system variables section. To go there, right click on Computer icon, select Advanced and then Environment variables.
There we found a Variable called ORACLE_HOME defined.
In the same place, we could see that oracle home had also been defined in Path variable.
However in 'Path', the Oracle Home was pointing to another directory.
We deleted the folder path in 'Path' variable.
After that we found that the database in tnsnames.ora was not defined.
So we need to add the Siebel database settings in tnsnames.ora 
After this we started Gateway and then Siebel server, Siebel ran without errors.