QCS fails to send calendar data for certain mailboxes with "Error: 0x8004010F" and "Unspecifie (72274)

- QCS fails to send calendar data for certain mailboxes
- The following errors can be seen in log files:

CalendarSender.log
18/03 17:08:07:299 | CalendarProcessorImpl.cpp(90)  | 3044 | *** EXCEPTION Exiting CCalendarProcessorImpl::ProcessObject
18/03 17:08:07:299 | CalendarProcessorObj.cpp(70)   | 3044 | Error:  0x8004010F

MAPIServ.log
18/03 17:08:07:268 | CalendarHelper.cpp(196)        | 292  | *** EXCEPTION Exiting CalendarHelper::GetCalendarFolder
18/03 17:08:07:268 | CalendarCollectorImpl.cpp(273) | 292  | *** EXCEPTION Exiting CCalendarCollectorImpl::OpenUserCalendar
18/03 17:08:07:268 | ACSMAPIServObj.cpp(866)        | 292  | Error:  0x8004010F

CalendarSender.log
23/03 10:08:32:520 | CalendarProcessorImpl.cpp(90)  | 3668 | *** EXCEPTION Exiting CCalendarProcessorImpl::ProcessObject
23/03 10:08:32:520 | CalendarProcessorObj.cpp(70)   | 3668 | Error: Unspecified error
 0x80004005

MAPIServ.log
23/03 10:08:32:489 | CalendarCollectorImpl.cpp(451) | 616  | Synchronize result: -2147467259
23/03 10:08:32:489 | CalendarCollectorImpl.cpp(400) | 616  | *** EXCEPTION Exiting CCalendarCollectorImpl::GetFolderMAPICookie
23/03 10:08:32:489 | CalendarCollectorImpl.cpp(167) | 616  | *** EXCEPTION Exiting CCalendarCollectorImpl::GetCalendarChanges
23/03 10:08:32:489 | ACSMAPIServObj.cpp(925)        | 616  | Error: Unspecified error
 0x80004005

1. Go to the problematic QCS server.
2. Stop 'Quest Collaboration Services Synchronization Service'.
3. Uninstall MAPI CDO (Microsoft Exchange Server MAPI Client and Collaboration Data Objects).
4. Download and install the latest version of MAPI CDO from http://www.microsoft.com/downloads/details.aspx?FamilyID=E17E7F31-079A-43A9-BFF2-0A110307611E
5. Start 'Quest Collaboration Services Synchronization Service'.