SBL-SRM-00016: Unable to initialize the Database environment -- Unable to start common api

I upgraded the Env to IP2016 with patchset7 on Windows 2012 R2. The installation and configuration was successful. On starting the Enterprise, I can see the processes are not getting created properly. On checking the logs, I can see multiple SvrTaskPersist & SvrTaskPersist logs. 

In these Logs I can see below error --

GenericLog GenericError 1 0000267559780d78:0 2017-07-26 15:56:36 (srmconn.cpp (908) err=1313725 sys=0) SBL-SVR-03005: No server connect string for Siebel Component SRBroker in Siebel Enterprise SBA_82_TEST, Siebel Server SIEBELSERVERSrmLayerLog Error 1 0000267559780d78:0 2017-07-26 15:56:36 Please check whether SRBroker is running on server SIEBELSERVER in enterprise SBA_82_TEST.

On checking SRBroker & SRProc logs, I can see below error --

GenericLog GenericError 1 0000265159780d78:0 2017-07-26 15:55:36 (srpdb.cpp (1000) err=2097168 sys=0) SBL-SRM-00016: Unable to initialize the Database environment -- Unable to start common api

This error can occur due to multiple reasons. I'll put step by step debug method here. Hope this helps.

1) Check if DB connectivity is proper. Check odbcsql connectivity

2) Check if you are using 32-bit client

3) If Unix server, then check .odbc.ini file and all its parameters

4) if SADMIN & SIEBEL user has sse_role assigned and password is not UNLIMITED

5) Login to srvrmgr and check if you can see the server. Set server servername for all the servers configured. This will check if all the servers are configured properly.

srvrmgr> list server

SBLSRVR_NAME  SBLSRVR_GROUP_NAME  HOST_NAME        INSTALL_DIR        SBLMGR_PID  SV_DISP_STATE  SBLSRVR_STATE  START_TIME           END_TIME  SBLSRVR_STAT
US
------------  ------------------  ---------------  -----------------  ----------  -------------  -------------  -------------------  --------  ------------
---------------------
SIEBSERVER                          HOSTNAME  D:\sba81\siebsrvr  4960        Running        Running        2017-07-27 07:53:40            16.7.0.0 [23
057] LANG_INDEPENDENT

1 row returned.

srvrmgr> set server SIEBSERVER

set server SIEBSERVER

           *
Do this for all the servers. If this error is coming, then either the siebns.dat is corrupted or the configuration was not proper. Reconfigure your Enterprise.

6) If all the servers are properly configured, then check the DSN setting.
srvrmgr> list param DSConnectString for named subsystem ServerDataSrc

PA_ALIAS                                                                      PA_VALUE

                          PA_DATATYPE                      PA_SCOPE                         PA_SUBSYSTEM                     PA_SETLEVEL
   PA_DISP_SETLEVEL                                               PA_EFF_NEXT_TASK  PA_EFF_CMP_RSTRT  PA_EFF_SRVR_RSTRT  PA_REQ_COMP_RCFG  PA_NAME

----------------------------------------------------------------------------  -----------------------------------------------------------------------------
---------------------------------------  -------------------------------  -------------------------------  -------------------------------  ---------------
----------------  -------------------------------------------------------------  ----------------  ----------------  -----------------  ----------------  -
---------------------------------------------------------------------------
DSConnectString                                                               DBCONN

                          String                           Subsystem                        Datasources Subsystem            Enterprise level
   Enterprise level set                                           Y                 N                 N                                    Data source Conn
ect String


1 row returned.

Here ServerDataSrc is incorrect. It should be the EnterpriseName_DSN.
change param DSConnectString=SBA_82_TEST_DSN for named subsystem ServerDataSrc

7) Check the USERNAME for the Enterprise and the value should SADMIN.
list parameter Username for server SIEBSERVER

8) Also check in SvrTaskPersist & SvrTaskPersist logs, if below error is found -
ORA-28365: wallet is not open --- We have to make sure that Wallet is open for all Siebel DBs

9) Even if error is not found, check with DBA if DB Wallet is in open mode. 
Also, check if Case Sensitivity is enabled for ids. Ask DBA to disable the Case Sensitivity, till the issue is resolved.

10) Parallel check if the 32-bit version of Oracle Client is installed and not 64-bit. Also, there should be only version of Oracle Client and that should be 32-bit.