Can't save WordPerfect file on laptop on network

When we try to save a file it says "Access Denied. You do not have rights to
do this." Then i click ok and a save box pops up and asks you to give it a
nmae or overwrite what is already in the file name box. When I click save it
says " ______. __.doc already exists. Replace?" When I click yes the
access denied box pops up again. This is on my daughter's desk top and it is
WOrd Peefect which came installed on the laptop but I do not have it on the
desktop. It is really frustrating. Also sometimes I can print from the
laptop & sometimes I can't. I have decent knowledge of my desktop but this
networking has really got me puzzled. I seem to do all I am suopsed to but I
still have problems. DO I have to do anything special to have access to
things on other desktops in XP? I haven't tried to save a WP file on my
desktop. IS there a good simple book that a layperson can read for help?
Thanks