Microsoft Outlook will not open .MSG files

Microsoft Outlook will not open .MSG files

November 11, 2007

Some systems running Microsoft Outlook XP or Outlook 2003 may suddenly stop opening attached .MSG files, even though these attachments opened correctly in the past. In this condition, double‑clicking the .MSG attachment inside Outlook has no effect or produces an error, while other attachment types continue to work normally. This behavior has been observed on systems where Google Desktop is installed and integrated with Outlook.

Symptoms

Outlook XP and Outlook 2003 exhibit one or more of the following when working with .MSG attachments:

  • .MSG attachments no longer open when double‑clicked.
  • The same .MSG file can be saved to disk and opened outside of Outlook.
  • Other attachment types (for example .DOC, .XLS, .PDF) open as expected.
  • The problem appears after Google Desktop has been installed or updated.

Cause

The issue is caused by a Google Desktop plug‑in that integrates with Outlook. When this add‑in is enabled, it interferes with Outlook’s normal handling of .MSG attachments. Systems that previously opened .MSG files without error begin to fail once the Google Desktop Outlook add‑in is active.

Resolution

Disabling the Google Desktop add‑in in Outlook restores normal behavior with .MSG attachments. The change can be performed entirely from within Outlook and does not require removing Google Desktop from the system.

Procedure

Follow these steps from within Outlook:

  1. Start Microsoft Outlook.
  2. From the menu bar, choose Tools > Options.
  3. Select the Other tab.
  4. Click Advanced Options….
  5. Click Add-In Manager….
  6. In the list of add‑ins, locate Google Desktop Search Outlook Add-in.
  7. Clear the checkbox next to Google Desktop Search Outlook Add-in.
  8. Click OK to close each dialog and return to Outlook.
  9. Close Outlook and start it again to ensure the change takes effect.
  10. Test by opening an attached .MSG file from an email message.

After the Google Desktop Outlook add‑in is disabled, attached .MSG files should open normally again in both Outlook XP and Outlook 2003.

Verification

This resolution was verified on:

  • Microsoft Outlook XP
  • Microsoft Outlook 2003

Testing was performed on November 8, 2007. In each case, disabling the Google Desktop Search Outlook Add-in immediately restored the ability to open .MSG attachments.

Notes

  • This article documents behavior observed with Google Desktop and Outlook as of November 2007.
  • If the add‑in is re‑enabled at a later time, the problem with .MSG attachments may reappear and the same steps can be repeated.
  • If similar symptoms occur without Google Desktop installed, a different add‑in or security product may be involved and should be tested separately.