Having problems receiving shared files (long post -sorry!!)

Okay ... I've been at this for 5 hours and desperately need some help!! I've
downloaded WLM version 8.1, and am trying to receive some shared files from a
fellow 8.1 WLM user. She has shared folders with plenty of people before. She
can syncronize the files for me on her end, but when I click on the "view
your sharing folders" icon or when I click on the "Tools" --> "Options" -->
"Sharing Folders" selections, I get the following message: "Your computer
does not support sharing folders." I don't know why. I have a legal version
of Windows XP which is automatically updated daily, I am the administrator of
the account, I am able to sign in, receive messages and individual files and
I can communicate with my contacts. It's the folders I can't receive and I am
driving myself crazy because of this. I even updated my windows manually and
disabled my Norton's Firewall to see if this would allow me to download the
shared folders, to no avail. There is a message on the "Troubleshooting
Sharing Folders" page which reads:

"You or your contact has a Messenger add-in that interferes with Sharing
Folders."
AND .....
"You haven't installed a security update that you need to have to share
folders."

What does this mean? Could this be why I cannot share folders? If there is
anyone out there who could help me out with this I would SO GREATLY
appreciate this!!
Thanks kindly for reading this LONG post (sorry!!)