Article ID: 2643084 - View products that this article applies to.
In Microsoft Outlook, you receive a meeting request from a Lotus Notes user or from another third-party email client. The message contains an attachment that has the following file name:
not supported calendar message.icsAdditionally, when you double-click to open the attachment, you receive the following error:
The file "not supported calendar message .ics" is not a valid Internet Calendar file.
The "not supported calendar message.ics" attachment is created when the original .ics file cannot be converted to an Outlook or Microsoft Exchange meeting type. The conversion fails if one or more of the following conditions are true:
To work around this issue, have the meeting organizer create a meeting that uses a recurring pattern that Outlook supports.
Or, if a Lotus Notes client connects to a Lotus Domino server, the following IBM website provides information about how to manage the recurring meeting options on the Domino server:
When a Lotus Notes recurring meeting is created, and this meeting has a Custom recurrence option, Lotus Notes generates an .ics file that only includes the RDATE property. If you save and open the .ics file attachment that is received in Outlook, you can see that the RDATE property is present. However, you notice that the RRULE property is not present.
Outlook and Exchange depend on the RRULE property to process an .ics attachment and generate the recurring meeting.
For more information about the RDATE and RRULE properties, visit the following page on The Internet Engineering Task Force (IETF) website:
The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.
Microsoft provides third-party contact information to help you find technical support. This contact information may change without notice. Microsoft does not guarantee the accuracy of this third-party contact information.
For information about how to contact any of the companies that are mentioned in this article, visit the following Microsoft website:
Article ID: 2643084 - Last Review: November 9, 2011 - Revision: 2.0