problem sharing calendars

All of the computers that we have in the office use
outlook 2000. They share folders and calendars, etc.,
using netfolders.
We have all the computers in our office sharing their
calendars with each other so that others receiving phone
calls can enter another's calendar from their own
computer to change an appointment, etc.
Everything was working fine except for one of the
computers. It seems to me that because computers need to
send out updates for their folders as e-mails, this
computer continues to send out updates it has already
sent. The other computers then end up doubling,
quadrupling, and multiplying almost all of the
appointments on the calendar, sending them back to the
original computer and then the original sends out new
updates for all of these entries.
So, you see my problem. We've got to the point that there
is so much information in this one calendar, I can't even
open it up on the original computer anymore.
Now, I've just told the original to stop sharing the
folder, and I think that will eliminate the problem, but
I need to set it back up again eventually. Any hints on
how I can get it to share this calendar without this
problem anymore?
Thanks...