Error
Microsoft .NET Framework, Unhandled exception has occurred in a component in your application. If you click Continue, the application will ignore this error and attempt to continue.
Violation of Primary Key constraint 'PK_tax901_ClientDateYear'. Cannot insert duplicate key in object 'dbo.tax901'. The duplicate key value is (XXX, Due Date XXXX).
If you are in the 901 Console when running a New List for a given Due Date, and this error occurs it is because the 901 Console can display only one record per client.
This error is caused by a duplicate record in the database for the particular Client that is indicated in the message For example in this case it's for Client ID=1355:
You can locate the client by running a basic Client List using only the Selection/Filter criteria of the Client ID, for example:
When the affected client is identified, open them in Central Console. Look for and delete any duplicated records such as email addresses; postal addresses; Income Tax or GST returns, or Matters.