To access to a production repository in Repository Viewer, the logged in user must have either of the following permissions:
- InTrust Organization Administrator
- Read permissions on the repository and index, is a member of the computer local AMS Readers group on the InTrust server that manages the repository, and is a member of the computer local AMS Readers group on the InTrust server that Repository Viewer connects to (these may be two different servers)
Run as Administrator option might also help to resolve this issue in case of UAC blocking the access.