Symptoms

Error message "Login failed for user 'NT AUTHORITYANONYMOUS LOGON'." is being received by users whenever they are trying to access one specific form. Error details:

Login failed for user 'NT AUTHORITYANONYMOUS LOGON'.
• Type:
SourceCode.SmartObjects.Client.SmartObjectException
• Source:
SourceCode.SmartObjects.Client
• Method Base
• Member Type:
Method
• Name:
GetSmartObjectReader
• Module
• Scope Name:
SourceCode.SmartObjects.Client.dll
• Declaring Type
• Full Name:
SourceCode.SmartObjects.Client.SmartObjectClientServer
• Stack Trace:

at SourceCode.SmartObjects.Client.SmartObjectClientServer.GetSmartObjectReader(SmartObject smartObject, ExecuteListReaderOptions options, Dictionary`2and propertyReference)

at SourceCode.SmartObjects.Client.SmartObjectClientServer.ExecuteListReader(SmartObject smartObject, ExecuteListReaderOptions options)

at SourceCode.Forms.AppFramework.FormsApiToXml.ToXmlList()

at SourceCode.Forms.AppFramework.FormRuntime.SmartObjectExecution(XPathNavigator nav, Boolean outputDependencies, SmartObjectClientServer svr)

at SourceCode.Forms.AppFramework.FormRuntime.WorkXmlToApi(String xml)

at SourceCode.Forms.Runtime.AJAXCall.ProcessRequest(HttpContext context)
 

Diagnoses

In K2 host server logs it is possible to see that the error we receiving is actually related with SQL service instance:

"Error","SmartObjects","10702","Error","SourceCode.SmartObjects.ServiceBroker OExecuteSmartObject]",
"10702 An error occurred in the %SQL_SI_NAME% Service Instance. Login failed for user 'NT AUTHORITYANONYMOUS LOGON'."

"10702","Error","SourceCode.SmartObjects.ServiceBroker OExecuteSmartObject]","10702 Retrying the %SQL_SI_NAME% Service Instance as the K2 Service Account did not resolve the issue. The server principal 'DomainUser' is not able to access the database '�_NAME%' under the current security context."

Based on these entries there are some issues with SQL service instance and it is necessary to verify SQL service instance using SmatObjects Services Tester tool and/or SQL server side permissions.
 

Resolution

It could be the case that SQL service instance configuration was changed for a specific DB used by your form, but security/permissions on the DB were not configured and all users did run into problems accessing the necessary information. Adjust permissions on SQL DB to resolve this problem.