Cannot open email links

I am trying to help a neighbor with an email problem.
She cannot open any email links that are presented in either an email or a web page.
She can open any web links, just not links to an email address.
She has Windows XP SP2 with full updates.

This is what I have done so far:

I ran the re-register command
"C:\PROGRAM FILES\OUTLOOK EXPRESS\MSIMN.EXE" /reg
I checked the file types
URL Hyper Text Transfer File Protocol
URL Hyper Text Transfer File Protocol with Privacy
and found
"C:\PROGRAM FILES\INTERNET EXPLORER\iexplore.exe" -nohome
I checked the path to iexplore.exe to make sure that is correct and uses the
double quotes.
DDE was checked and in the boxes below it read:
#1:
"%1",,-1,0,,,,
#2
IExplore
#3 (blank)
#4
WWW_OpenURL

I also checked the URL mail to Protocol
and found
C:\Program Files\Outlook Express\msimn.exe as the program
DDE was checked
application was "msimn"
type was "system"

I went to the registry
HKEY_LOCAL_MACHINE\SOFTWARE\Clients\Mail\Outlook Express
and found
C:\PROGRAM FILES\OUTLOOK EXPRESS\MSOE.DLL for the dll path (and msoe.dll is there)
just as suggested in MS KB Q306098

Anyone have any more suggestions or ideas?