CDM - Cannot login due to Unknown server error

Technote (troubleshooting)


Users cannot login to CDM due to an "Unknown server error"; checking logs shows a "Ibm.CognosDM.Services.WebHost.Global - (null) Could not impersonate the data sources user ? ? ? " error.


When trying to log in, you will see an "Unknown server error" in the login screen; further checking the AllErrors log, the following error will be present :

[11] FATAL Ibm.CognosDM.Services.WebHost.Global - (null) Could not impersonate the data sources user ? ? ? Ibm.CognosDM.DataSources.DataSourceUnavailableException: Could not impersonate the data sources user ---> Ibm.CognosDM.Windows.Impersonation.ImpersonationException: Cannot login using the provided credentials
at Ibm.CognosDM.Windows.Impersonation.ImpersonationUtil.LogonUser(WindowsCredentials credentials, LogonType logonType, LogonProvider logonProvider)
at Ibm.CognosDM.Windows.Impersonation.ImpersonationUtil.GetImpersonationContext(WindowsCredentials credentials, LogonType logonType, LogonProvider logonProvider)
at Ibm.CognosDM.Windows.Impersonation.ImpersonationUtil.ImpersonateExecutionContext(WindowsCredentials credentials, LogonType logonType, LogonProvider logonProvider, Action codeToExecute)
at Ibm.CognosDM.BusinessLogic.ExternalData.DataSources.DataSourceImpersonator.RunUnderWindowsCredentials[T](Func`1 func)
--- End of inner exception stack trace ---
at Ibm.CognosDM.BusinessLogic.ExternalData.DataSources.DataSourceImpersonator.RunUnderWindowsCredentials[T](Func`1 func)
at Ibm.CognosDM.BusinessLogic.Cache.ExpirationPolicies.EefExpirationPolicy.Initialize(CacheItemPolicy cacheItemPolicy, Object[] dynamicParameters)
at Ibm.CognosDM.Cache.CacheZone.MemoryCacheZoneManager.InitializeExpirations(CacheItem cacheItem)
at Ibm.CognosDM.Cache.CacheZone.MemoryCacheZoneManager.Add(String key, Object value, CacheItemPolicy policy)
at Ibm.CognosDM.Cache.DualCache.LoadMemoryCacheFromPersistentCache(String zone)
at Ibm.CognosDM.Cache.DualCache.Start()
at Ibm.CognosDM.Services.WebHost.Global.Application_Start(Object sender, EventArgs e)


This is caused by an incorrect username/password for the data sources user.


CDM 10.2.x

Diagnosing the problem

Try to log in with any user - the error above will be generated.

Resolving the problem

Edit the configuration file (located in your <CDM install folder>\Config folder) and check that the username and password for the data sources user (DataSourcesCredentials) are correct.

CDM 10.2.0, the appropriate configuration file is CDM.config
CDM10.2.1 +, the appropriate configuration file is Credentials.config

<DataSourcesCredentials enabled="true" userName="username" password="password" />
<ActiveDirectoryImportCredentials enabled="true" userName="username" password="" />

After changing the credentials to the correct values, restart IIS and try to log in to CDM again.

Document information

More support for:

Cognos Disclosure Management
Cognos Disclosure Management

Software version:


Operating system(s):


Software edition:

All Editions

Reference #:


Modified date:


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