When sending messages as another user the following errors might be received:

  • Outlook in Cached Mode

    Permission Error 2
  • Outlook in Non-Cached Mode

    Permission Error 1
  • OWA

    OWA Error

To fix the issue perform the following:

  1. Double-check if you have Send As permissions on the mailbox you are sending from. Refer to the article How Do I Enable Send As Or Full Access Permissions On Exchange Account? for instructions.
  2. If permissions are correct on the server you should no longer receive the error in OWA or Outlook in Non-Cached Mode. Outlook in Cached Mode might still not work due to incorrect cached entries. Make sure that the correct address is chosen from Global Address List.

    Other Email AddressGAL Lookup