Encryption Desktop does not send messages if Cached Exchange Mode is disabled


Article ID: 209142


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Desktop Email Encryption Desktop Email Encryption, Powered by PGP Technology


If Cached Exchange Mode is disabled in Outlook, messages appear to be sent successfully and appear in Sent Items but they are not actually sent.

This only occurs if Outlook for Office 365 or Outlook for Microsoft 365 is connected to Exchange Online. It does not occur with on-premise Exchange.

This issue occurs if PGP Tray is running. It occurs with both encrypted and unencrypted messages.


Symantec Encryption Desktop 10.4.2 to 10.5 MP1.


Upgrade to release 10.5 MP2 or above where this issue is resolved.

If you cannot upgrade, ensure that Cached Exchange Mode is enabled in Outlook. Cached Exchange Mode is enabled by default. To check that Cached Exchange Mode is enabled, please do the following:

  1. Open Outlook.
  2. Click on the File menu.
  3. From the Account Information page, click on Account Settings and then from the dropdown list click on Account Settings :
  4. From the Email Accounts list, double click on your email address:
  5. From the Exchange Account Settings page, ensure that the Use Cached Exchange Mode option is enabled:
  6. If you made changes, click the Next button and then the Done button, otherwise close the page.
  7. From the Account Settings page, click the Close button.

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