network folder and file sharing

We are running windows server 2000. I tried to map users to a specific
server drive today and received a "contact administrator you don't
have access to the folder" error. After trying unsuccessfully to do map
this drive on several users computers I "assumed" the problem was
they needed to be added to sharing group. I also noticed there were
quite a few people already in the group. I added "everyone" to the
shared group with rights to view and execute, read, list folders. No
write and modify privileges were extended. Shortly afterwards I
reconsidered and decided to remove the "everyone" only and address
individual needs separately. According to all reports the
aforementioned folders should have been accessible by each user I
attempted to map, but were not. Secondly, would the "everyone"
addition and removal reset access rights? Thanks! Just trying to figure
out the why of the situation.