# Upgrade issues with ObjectDataSource Component after Telerik Reporting R3 2016

## Environment

<table>
	<tr>
		<td>Product</td>
		<td>Progress® Telerik® Reporting</td>
	</tr>
    <tr>
		<td>Version</td>
		<td>R3 2016 and later</td>
	</tr>
	<tr>
		<td>Report Item</td>
		<td>ObjectDataSource Component</td>
	</tr>
</table>

## Description

As of [R3 2016](https://www.telerik.com/products/reporting/documentation/upgrade/2016/r3-2016#api-breaking-changes) we provide stricter rules for external assemblies used by reports to get data. This is a breaking change that may lead to the following error on preview, even after running the [Upgrade Wizard](https://www.telerik.com/products/reporting/documentation/designing-reports/report-designer-tools/desktop-designers/visual-studio-report-designer/upgrade-wizard).

## Error Message

```
An exception has occurred while processing 'REPORTNAME' item:

System.Security.SecurityException: The assembly "EXTERNAL_ASSEMBLY_TYPE" is not permitted to be used by an ObjectDataSource component. Please include it in an AssemblyReferences element in the Telerik.Reporting configuration section of your application configuration file.
```

## Possible Causes

* The assembly supposed to be used by the ObjectDataSource is not referenced in the application configuration file;

* The assembly is incorrectly referenced;

## Solution

The ObjectDataSource component is designed to read the assembly information from the current project's configuration file. Thus, the assembly to be used by the [ObjectDataSource](https://www.telerik.com/products/reporting/documentation/designing-reports/connecting-to-data/data-source-components/objectdatasource-component/overview) component must be referenced in the **AssemblyReferences** element in the **Telerik.Reporting configuration section** of your application configuration file.

1. The Standalone Report Designer tool's configuration file, if you intend to use an ObjectDataSource component - [Extending Report Designer](https://www.telerik.com/products/reporting/documentation/designing-reports/report-designer-tools/desktop-designers/standalone-report-designer/configuration/extending-report-designer);

2. The configuration file of the project containing the Telerik Reports.

3. The configuration file of the desktop application displaying/processing programmatically the report or the configuration file of the Reporting REST|WCF Service project, this place is where reports are handled for web viewers.

## Notes

It is recommended to keep reports in a separate project e.g. ClassLibrary project. *The ObjectDataSource component's settings can be added automatically by re-running the [ObjectDataSource Wizard](https://www.telerik.com/products/reporting/documentation/designing-reports/report-designer-tools/desktop-designers/tools/data-source-wizards/objectdatasource-wizard) in Visual Studio Report Designer.*

## See Also

[Connecting the ObjectDataSource component to a Data Source](https://www.telerik.com/products/reporting/documentation/designing-reports/connecting-to-data/data-source-components/objectdatasource-component/connecting-the-objectdatasource-component-to-a-data-source)

[ObjectDataSource: Configuration](https://www.telerik.com/products/reporting/documentation/designing-reports/connecting-to-data/data-source-components/objectdatasource-component/overview#configuration)