Depends on the precise steps you used, which you failed to post. Normally
this is end user error.

Answer: No - leastwise none that we've ever encountered either via the
Outlook export wizard or our own products.  You didn't mention how many
contacts are involved vis-a-vis how many in folder versus how many are being
exported.

Since I suspect that you are encountering an export issue exporting your
contacts based on the subject - some "very prelim" questions in advance of
some more specific info are:

#1 - Is the number of contacts being exported always the same? If yes -
first clue would be to look for the contact that follows the last one
exported assuming that your view is in the same sequence used when
exporting. If no, is the file being exported to located on a local or
network drive? How often is your Outlook checking for email (ergo - is it
kicking in while the export process is in progress especially if you also
have some add-ins running that pre-process incoming email). If the number of
records being exported is not identical in each run - then odds are that the
issue is not "data related" but rather is an operational issue.

#2 - If the number of contacts exported is the same each time, does the
number stay the same when a different output file type is used (i.e. CSV, MS
Access etc)

#3 - Have you run a ScanPST on your contact folder (if not using Exchange)
to determine if there is a problem with your PST folder? If using Exchange,
there is always a possibility that one or more contacts within the personal
store has/have become corrupted - while not "common" - it is an issue that
we've seen more times that we'd like causing various kinds of issues. (A
corrupted contact will/may not impact day to day use if you don't access the
corrupted record but will if attempting to go through the entire list.
Solution - find/delete corrupted contact(s)).

A caveat about ScanPST since you're using O'2007. If using a PST file which
has been upgraded from a prior version of Outlook - ScanPST, more often then
not will report errors that are not reported if run using the version of
ScanPST where the PST file was created (original PST created as '97-2002 and
to a somewhat lesser extent '2003)

#4 - Is a custom form in use in the folder (or has a custom form been used
previously for some or all of the contacts?)

Karl
___________________________________________________
Karl Timmermans - The Claxton Group
ContactGenie - Importer 1.3 / DataPorter 2.0 / Exporter
"Power contact importers/exporters for MS Outlook '2000/2007"
http://www.contactgenie.com