Go to Tools - Trust Center, select "Add-ins" go to the bottom of the
page, you'll see a drop down titled "Manage:"
select "Exchange Client Extensions" from the drop down, click "Go" -
remove the check from "FaxExtension" then "OK"
That should disable that annoying msg
Unfortunately the above fix will only remove the message until you
restart your machine. To remove the message permanently follow these
two steps with extreme caution! (see backing up the
registry) ...works for Win Vista & Outlook 2007...
Go to the "FaxExtension" location mentioned in the post above and
select "Install" - right click and rename "FAXEXT.ECF" to
"FAXEXT.ECT.OLD" (in case you need it at some point??) Say yes to the
warning.
Click on Start - All Programs - Accessories - Run. Type in "regedit"
then "OK" and go to the following location:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Exchange\Client\Extensions
Double click "FaxExtension" and highlight "4.0;C:\WINDOWS
\system32\fxsext32.dll;1;00000100000000" right click and select "Cut"
then save it somewhere e.g. Word. (in case you need it at some
point??)
The check box "FaxExtension" will be removed from the list of "Add-
ins" and the Error msg should be removed on a restart as well.
Regards
Jerry