1. Open IIS Manager
2. Open Default Web Site\SecurityTokenService and switch it to Content view.
3. In the Services folder, browse the SecurityTokenService.svc in IE. (right click and click Browse)
4. On the IE window, if everything works properly, it should say "You have created a service".
5. Do the same for RPservice. Browse RPService.svc in IE and it should also say "You have created a service"
If step 5 failed, please go to ION Enterprise/application directory and share RPServices with Everyone.