Authentication failed issue in OBIEE11G

ISSUE:
Starting Presentation Services fail with the error:

[OBIPS] [ERROR:1] [] [saw.security.odbcuserpopulationimpl.

getbisystemconnection]

 [ecid: ] [tid: ] Authentication Failure.
Odbc driver returned an error (SQLDriverConnectW).
State: 08004.  Code: 10018.  [NQODBC] [SQL_STATE: 08004] [nQSError: 10018]

 Access for the requested connection is refused.
[nQSError: 43113] Message returned from OBIS.
[nQSError: 43126] Authentication failed: invalid user/password. (08004)[[

Also connecting to the metadata repository (RPD) in online mode fails with similar error.
Looking through the BI server log, nqserver.log, you may find an error message similar to the following:

[OracleBIServerComponent] [ERROR:1] [] [] [ecid: 

0001J1LfUetFCC3LVml3ic0000pp000000] [tid: 1] 
[13026] Error in getting roles from BI Security Service:  
'Error Message From BI Security Service: [nQSError: 46164]

 HTTP Server returned 404 (Not Found) for URL .' ^M

RESOLUTION:

• Connect to WebLogic Server (WLS) Console -> Deployments. Ensure that all deployed components are in 'Active' state.
  
• If any of the components is in 'Prepared' state, select that application and then click on "start servicing all requests"
  
• Restart BI Server and Presentation Services
  

In some cases, the following additional step might be needed to resolve the issue.

• Access the Enterprise Manager Fusion Middleware control: http://<host.domain>:port/em
  
• Navigate to Business Intelligence -> coreapplication
  
• 'Capacity Management' tab -> 'Scalability' sub-tab
  
• Click on 'Lock and Edit Configuration' button
  
• Enter the IP address in the 'Listen Address' field
  
• Click on 'Activate Changes' followed by 'Release Configuration' buttons
• Restart BI Server and Presentation Services
  

Also check these My Oracle Support (MOS) documents for more clues and information.
1387283.1 Authentication failed: invalid user/password
1251364.1 Error: "[nQSError: 10018] Access .. Refused. [nQSError: 43126] Authentication Failed .." when Installing OBIEE 11g
1410233.1.1 How To Bind Components / Ports To A Specific IP Address On Multiple Network Interface (NIC) Machines