You receive an "Unable to connect to the data" error message when you try to update data in a Visio 2010 diagram, and you use a connection in an ODC file to a SQL Server that requires you to provide credentials for SQL Server Authentication
You have an Office Data Connectivity (ODC) file that provides a connection to a data source on a Microsoft SQL Server, and this server requires you to provide credentials for SQL Server Authentication.
You create a diagram in Microsoft Visio 2010.
You import data into the diagram by using the ODC file. To do this, when you are prompted for the URL or the UNC, you type the path of the ODC file, and then you finish the Import wizard.
When the import of the data is finished, you click the Data tab, and then you click Refresh All.
In this scenario, the data is not updated in the diagram. Additionally, you receive the following error message:
Unable to connect to the data.
To work around this behavior, follow these steps:
Save the Visio diagram.
Start Visio, and open the diagram that you saved in step 1.
Click Refresh on the Data tab.
When you are prompted, type your SQL Server credentials for the data source.
For more information about connections that are stored in Office Data Connectivity (ODC) files, visit the following Microsoft TechNet website: