You may see this error when you try to accept recurrence meeting ,which time was been updated.

To resolve this issue:

  1. On the BES Server, click Start > Run and type regedit.
  2. Navigate to the following registry HKEY_CURRENT_USERSoftwareMicrosoftOffice11.0OutlookOptionsCalendar.
  3. Right-click the Calendar folder and click New > DWORD Value.
  4. Type DisableMeetingRegeneration and press ENTER.
  5. Double-click the new key and type 1 in the Value data field of the Edit String screen.
  6. Click OK and close the Registry Editor.

Go to your device and delete BIS CICAL service book

To delete CICAL on BB device go to Settings–>Advanced Options –> Service Books
Locate BIS CICAL and delete it.

Than go to your BlackBerry Enterprise server , right click on user and pres “Resend Service Book”

Restart your device and meeting accepts should start working.