If you are getting the below message while Data Package reads data from the source database table then this normally means the operation has taken more than 5 minutes which is the default timeout value (~300 seconds). 

Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding.

To increase the timeout value please add the following line to the AppSettings section of the Analyzer Web.config file in \program files\analyzer\web folder. Below example sets the timeout to 1200 seconds, you may want to adjust it accordingly.

<add key="DataPackageTransferTimeout" value="1200" />