Good Morning.
I have additional information that may help get this issue resolved.
I changed the IIS application pool to use NetworkService and the "odd" login screen became a normal looking login screen. However, I am still not able to log in.
Here is what is happening:
When I use http://[onestream]:50001/OneStreamWeb/OneStreamWindowsApp.aspx, I get redirected to OneStreamWeb/NativeLogin.aspx. This screen prompts for a username/password. So, I enter the only username/password I know (Administrator/OneStream) and I get a message that says "Unable to log on user 'Administrator'. The password was reset and needs to be changed." I have no idea how to change the password, since I cannot log in to OneStream. I have tried other URLs and they all seem to redirect me to this NativeLogin page.
Any help would be appreciated.