Stored Credentials for database on report server

I deployed a report to the report server. The credentials are Windows Authentication. I was able to set up a subscription. Changes were required and I uploaded the new .rdl file and deployed it. I can not set up a subscription now. I get a message stating the credentials are not stored, but they are. I also deployed  the old .rdl file that did have subscriptions set up and get the same message that the credentials are not stored. Any ideas?