Are you using BlackBerry Enterprise Server or BlackBerry Professional? The most likely cause is that the BES is unable to use the CDO.DLL file to perform Calendar functions. What we need to do is ensure the cdo.dll file is registered correctly, to confirm these settings please perform the following tasks:
To check if the CDO.dll file is registered on the BlackBerry Enterprise Server- Click Start > Run and type regedit. Click OK.
- Click on the HKEY_CLASSES_ROOT folder to expand the folder.
- Verify whether you have the following registry key:
HKEY_CLASSES_ROOT\CLSID\{3FA7DEB3-6438-101B-ACC1-00AA00423326}
If you have this registry key, the CDO.dll file is registered on the BlackBerry Enterprise Server.
To check the location for the registered CDO.dll file- Double-click the folder for the registry key.
- Click the InprocServer32 folder.
- Check the path beside (Default), as shown below. This is the path of the registered CDO.dll file.
If this file is missing or displayed incorrectly you need to run the following command to register the cdo.dll file:
regsvr32 "c:\Program Files\Exchsrvr\bin\cdo.dll"
Other common causes are:
1. Send As permissions have been revoked. This can be confirmed as user won't be able to send emails from their device.
2. The device may have a corrupt service book. Try resending the service books from the server
3. The meeting request was deleted, and then emptied from the Deleted Items folder.
4. The meeting request was deleted by a delegate.
5. The meeting request was deleted and Microsoft Outlook was closed while the Empty the Deleted Items folder upon exiting option was selected.
6. The user has Outlook configured to deliver emails to an offline PST causing items to be removed from the Exchange server