Scenario #A - User launches Controller. User receives error message. Scenario #B - User launches Controller. User then receives database selection menu. User selects their database. User then receives error message.
- An error occurred while trying to access server
Event Viewer (Application Log)
Depending on the exact scenario which caused the problem, you will typically find a unique error message recorder inside the application log (inside the Windows Event Viewer).
This is a generic error message. Therefore there are a large number of different potential causes:
- Scenario #1 - The Controller SQL login (for example 'fastnet') cannot read the required information (for example, the 'dbversion') from the Controller database table(s)
- For example, see separate IBM Technote #1345403
- Scenario #2 - The client PC is configured to *not* use 'SelectDb', but there is no database connection named 'Default'
- Scenario #3 - The client PC cannot resolve the WSSUrl value inside 'Client Distribution Server' configuration
- Scenario #4 - The application server has not been configured correctly
- Scenario #5 - Cognos 8 security is enabled, but not configured correctly
- For example, see separate IBM Technote #1347413
- Scenario #6 - Gateway server has not been correctly configured
- Scenario #7 - Database server offline, or other connection problem with database server
- Scenario #8 - Incorrect Provider specifed in Database Connections
- Scenario #9 - Dispatcher configuration is incorrect
- For more information, see separate IBM Technote #1375638
- Scenario #10 - NTFS permissions problem on Controller server's installation folder
- For more information, see separate IBM Technotes #1345788 and 1345789.
- Scenario #11 - Incorrectly configured Oracle server
- For more information, see separate IBM Technote #1346220
- Scenario #12 - COM+ Security problem on Controller application server
- For more information, see separate IBM Technotes #1367316 & 1371331.
- Scenario #13 - NTFS permissions problem on Controller server's TEMP/TMP folder
- For more information, see separate IBM Technote #1345976
- Scenario #14 - Controller application server cannot locate the SQL server
- For more information, see separate IBM Technote #1347102
- Scenario #15 - SQL database name has at least one comma in its name
- For more information, see separate IBM Technote #1423649
- Scenario #16 - SelectDb has not been configured correctly.
- For more information, see separate IBM Technotes #1346525 &1346971
- Scenario #17 - NTFS permission problem on folder c:\inetpub\wwwroot\web.config
- For more information, see separate IBM Technote #1395843
- Scenario #18 - Missing 'wwwroot' folder on webserver
- For more information, see separate IBM Technote #1437698
- Scenario #19 - End user's Windows Regional Settings are invalid
- For more information, see separate IBM Technote #1403299
- Scenario #20 - Incorrect "Data Source" entry for SQL database server instance
- For more information, see separate IBM Technote #1587926
- Scenario #21 - COM+ Windows user's password has expired (e.g. inside Active Directory)
- For more information, see separate IBM Technote #1370816
Scenario #A - User does not see database selection screen:
Most of the above causes are possible.
Scenario #B - User selects database and then receives error:
Most of the above causes are possible (except #2). However, the most likely (so this is where you should start looking) is cause #1.
Diagnosing The Problem
The screen message is a generic one. Therefore, there are a large number of IBM Technotes that could explain your cause/solution. To help narrow down the cause, try the following suggestions to help with troubleshooting:
(i) Event Viewer Application Log
- Start - Run - "EventVwr" <Enter>
- Open the 'Application Log"
- Search for error messages at the time when the problem occurred.
- Search the IBM Technotes for any text inside here.
(ii) Test the ASP.NET-COM+ interface website
- On the client device, launch the ASP.NET-COM+ interface website (http://servername/cognos8/controllerserver/ccrws.asmx)
- If working correctly, then you should be presented with a list of approximately 250 COM+ objects. However, if you get an error message, search the IBM Technotes for any text inside the error.
However, this IBM Technote shall also describe another test, which specifically relates to one cause:
To confirm that this is the problem, do the following:
- Launch 'Controller Configuration' and open 'Database Connections' section
- Highlight database
- Click 'test' icon (green 'tick') - is this succesful?
- Open the database UDL file (inside C:\Program Files\Cognos\c8\data) and click 'test connection'
- Click 'DbConv' icon (green 'play' button)
- is the value of the DbVersion zero (bad) or a high number (good)?
- Is the database 'actual' version the same as the 'dbconv' version (good)?
Also, assuming that you have a problem, you can narrow down the cause of this by opening the Windows Event Viewer, and opening the 'application log'. For example:
- Login failed for user 'fastnet'. Reason: The password of the account has expired. [CLIENT: 10.5.1.15]
In this case, you would have to change the SQL 2005 server's policy on the SQL login (e.g. 'fastnet') so that the password does not periodically expire
Resolving The Problem
TIP: A common cause of problems here is if the SQL login user (for example 'fastnet') has been given too many SQL rights. For example, it has 'System Administrators' (sysdba) ticked/enabled. To solve this, untick the server role 'system administrators'.
- See KB#1040325 for full details.
Open the client PC's 'ccr.config' file (inside %appdata%\cognos\ccr) with NOTEPAD.EXE. Search for 'SelectDb'. If this is set to 'False' then a database connection called 'Default' is necessary. Alternatively, simply change the value to 'True' and re-test.
- For full details, see separate KB article #1027807
- Ensure that the client PC can resolve the WSSUrl path/value inside the Client Distribution Server configuration section of 'Controller Configuration'.
- Ensure that there is not a network policy/device blocking client access to the server
- For example, ensure that there is not an 'Intrusion Protection System' device on the application server.
- In IIS, verify that ASP.NET (or aspnet_client) is installed/configured correctly
- Check the COM+ settings (Uncheck the "Enforce access checks..." tickbox and try adding 'everyone' to the list of users that can access the com+ package
- Open a browser window and browse the following URL: http://servername/cognos8/controllerserver/ccrws.asmx
- If it works then try doing the same thing from the client PC
- If it doesn't work, the error message will indicate the cause of the problem
- Doublecheck the configuration programs (both 'Cognos' and 'Controller' configuration), make sure to replace any occurrence of 'localhost' with the actual servername used.
- Make sure that the 'web' user has access to the 'temp' folder.
See separate KB articles #1031381, #1036125 and #1023494 for more details.
If the Controller Server Authentication is set to Series 8, confirm that Controller Administrators and Controller Users have been added to Cognos 8 and are configured with appropriate permissions
Verify that the user login must be a member of the groups above.
- If using Series8 authentication, CAF may need to be be True
- If using 'Native' security, CAF may need to be set to 'False' in order to get Standard Reports to work correctly.
- See separate KB article #1036430.
See separate KB article #1037507.
Cannot resolve SQL instance name - see separate KB article #1032887.
Cognos Controller Configuration - Database Connections, ensure that the Provider for the database is correct, i.e. SQLOLEDB.1 for a SQL Server database connections or ORAOLEDB.ORACLE.1 for an Oracle database.
The attached document ('04. An error occurred while trying to access server - Explanation and Fixes - July2006.pdf') gives a description of some of the most popular causes.
15 June 2018