Recurring appointments sent to Exchange are received as email

  • 7007784
  • 04-Feb-2011
  • 03-Jul-2012

Environment

Novell GroupWise 8
Novell GroupWise 2012
Microsoft Exchange 2007
Microsoft Exchange 2010

Situation

  • Recurring appointments sent internally work fine.
  • Recurring appointments sent to Exchange 2003 work fine.
  • Recurring appointments sent to Exchange 2007 or 2010 arrive as emails instead of as appointments.
  • The received email has a attachment with a .ics extension.
  • Attempts to open the email result in the following error: "The file "not supported calendar message.ics" is not a valid Internet Calendar file.".
  • Recurring Reminder notes, attempted to be imported into the Outlook Calendar, will also encounter the following error: "The file "not supported calendar message.ics" is not a valid Internet Calendar file.".

Resolution

Note:
 
GroupWise 2012 addresses many scenarios that had previously displayed the results of having the appointment arrive as email.  If after upgrading to GroupWise 2012 and applying the latest available Service Pack the problem continues to exist, please open a call with Novell Technical Services.
 
4/19/2011
Development has added some work around fixes to the GWIA for this issue.  Novell Technical Services, may be contacted to get newer code.  The Service Request may be refunded, if only new code is desired.  If the fix is believed to cause more problems then it fixes, the fix may be pulled to undergo further research.  Please see the Additional Information section for back ground information relating to this issue.

Note: After the fix is in place, there may still be cases that are not recognized by Exchange 2010 / Outlook 2010 as valid iCal files, working event instances are still created if you save the .ics attachment file and import the saved file.

Work around code fixs for GWIA for Exchange 2010 and Outlook 2010:
Whenever possible, we generate a simple RRULE.
For example, for an annual event a RRULE is generated with MONTHLY frequency and 12 month interval.
When necessary, we generate a RRULE with multiple values for BYMONTHDAY or BYYEARDAY.
Finally, we create a one-instance RRULE and add a RDATE parameter for the remaining instances.

Additional Information

Microsoft has historically not fully supported recurring appointments and this may be a continuation of that.  However, Novell is researching why the problem doesn't occur against Exchange 2003 and only occurs against Exchange 2007 and 2010.

Update as of 4/14/2011
If the recurring appointment instances span more than a year, an iCal is generated with RDATE instead of RRULE.
This was reproduced by sending a monthly appointment with 32 instances to Exchange 2010, accessed with a Outlook 2010 client.  It appears the Exchange/Outlook still does not support a RDATE without a RRULE.
The same recurring appointment can be sent to another external mail system and it appears to be handled correctly by the calendar plugin on the Mozilla Thunderbird mail client.