Thanks for the help, Roderunner. If I use WLM to open the calendar appointment request from Office Outlook, there is no visible information regarding the calendar. If I press the "Add to Calendar" button, I am shown the appropriate screen but the day and time shown reflect whatever the actual date and time are, not the date and time of the requested appointment.
In the following, I have changed the names for privacy, but the message from my colleague is being sent to me at three accounts and my wife.
On the WLM screen, there is an attachment shown, ATT00018.txt. I am thinking that it contains both the text of the message (which does appear) and the calendar request (which does not). A similar massage without the text showed in WLM as blank but had a similar .txt attachment except for the info on site visit, Mardi Gras World, etc. The contents of the .txt attachment with the text and calendar are:
BEGIN:VCALENDAR
METHOD:REQUEST
PRODID:Microsoft Exchange Server 2010
VERSION:2.0
BEGIN:VTIMEZONE
TZID:Eastern Standard Time
BEGIN:STANDARD
DTSTART:16010101T020000
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
RRULE:FREQ=YEARLY;INTERVAL=1;BYDAY=1SU;BYMONTH=11
END:STANDARD
BEGIN

AYLIGHT
DTSTART:16010101T020000
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
RRULE:FREQ=YEARLY;INTERVAL=1;BYDAY=2SU;BYMONTH=3
END

AYLIGHT
END:VTIMEZONE
BEGIN:VEVENT
ORGANIZER;CN=Colleague in Washington:MAILTO:
[email protected]
ATTENDEE;ROLE=REQ-PARTICIPANT;PARTSTAT=NEEDS-ACTION;RSVP=TRUE;CN=Me
- Personal:MAILTO:
[email protected]
DESCRIPTION;LANGUAGE=en-US:\n\n-----Original Appointment-----\nFrom: Michel
le Stevenson\nSent: Friday\, November 14\, 2014 10:38 AM\nTo: Colleague in Washingon
\; My wife\; Me at work\; Me at gmail
<mailto:my gmail.com acct>)\nSubject: ICS Conference Call\nWhen: M
onday\, November 24\, 2014 10:00 AM-11:00 AM (UTC-05:00) Eastern Time (US
& Canada).\nWhere: 10:00 AM Eastern / 9:00 AM Central\n\n\nAgenda\n\n1.
Confirmation of site visit\n2. Update of Mardi Gras World\n3.
Status of Basilica\n4. Review of Sponsor Brochure\n\n
SUMMARY;LANGUAGE=en-US:FW: ICS Conference Call
DTSTART;TZID=Eastern Standard Time:20141124T100000
DTEND;TZID=Eastern Standard Time:20141124T110000
UID:040000008200E00074C5B7101A82E0080000000060DA1D1BF7FFCF01000000000000000
0100000008F4BE0311F4D9B419333A035102C250B
CLASS

UBLIC
PRIORITY:5
DTSTAMP:20141114T153819Z
TRANSP:OPAQUE
STATUS:CONFIRMED
SEQUENCE:1
LOCATION;LANGUAGE=en-US:10:00 AM Eastern / 9:00 AM Central
X-MICROSOFT-CDO-APPT-SEQUENCE:1
X-MICROSOFT-CDO-OWNERAPPTID:399423454
X-MICROSOFT-CDO-BUSYSTATUS:TENTATIVE
X-MICROSOFT-CDO-INTENDEDSTATUS:BUSY
X-MICROSOFT-CDO-ALLDAYEVENT:FALSE
X-MICROSOFT-CDO-IMPORTANCE:1
X-MICROSOFT-CDO-INSTTYPE:0
X-MICROSOFT-DISALLOW-COUNTER:FALSE
BEGIN:VALARM
ACTION

ISPLAY
DESCRIPTION:REMINDER
TRIGGER;RELATED=START

T15M
END:VALARM
END:VEVENT
END:VCALENDAR
It is as if WLM is not recognizing VCALENDAR and REQUEST.