Excel Online not working in PBIRS

We downloaded and installed the PBIRS preview for August. Pbix files work as do RDL reports. I can upload Excel files as well. We also installed OOS on the test PBIRS server and configured using http. The issue I have is when i click to open the Excel file, I receive an error: "Unable to Open the file. We couldn't find the file you wanted. It's possible the file was renamed,moved or deleted." The file was not any of these suggestions. It is where I specified on upload. I have searched for this issues but i get info related to SharePoint, which this is not. What am I missing? Thanks!