Unable to establish connection in report testing

[Chuck Harrington]

I need to test some extensive code behind logic for a report I am developing, so I added a Windows form project to my solution that contains the class library with the report in it.  I added the necessary reference to my code library and set the window form as the start up form.  I added the Report Viewer and the correct reference to my report in the Report property.  So far no problem.  When I attempt to generate the report however, I get the following message "An error has occurred while processing Report 'report object name'  Unable to establish connection to the database." etc.  I have verified my database connection.  I have no problem previewing the report from my class library.  It generates just fine but with invalid data, thus the need to single step through my logic.  What am I missing in setting up this testing environment.  thanks in advance.

[Steve]

Hi Chuck,

The error message is correct - the report cannot find the connectionString. If the reports are defined in a class library, always remember to copy the corresponding connection string entries from the class library's config file to the application's config file. Otherwise at runtime when the application's config file is respected the Settings object will not be able to find such connection strings and will return the default value from its metadata. More information is available in the Using connectionStrings from configuration file KB article.

Greetings,
Steve
the Telerik team