Just for kicks I changed the server back to workgroup. After doing that I logged back in, I am able to view the reports.

I can't open the report myself. We can view the report by pdf or html, but we are unable to open any of them.

Yes, the sql reporting server is on the same server as the IIS/SQL server.

User uses the reporting services daily. User could not open up the report on Friday.

Sorry, I do not know what you mean by connectionstring? I am not familiar with SQL.

It is sql authentication.