Offline Files - GPO

I am having problems with users when the log off. I have disabled the policy
for offline files but users files are still synchornizing on log off and log
on. How can I disable this? Also, what is the proper procedure for
configuring the use of offline files if i want specific users to be able to
take files offline? I have created my OU structure to distinguish the 2
groups, who can take files offline, and who cant. How would I configure
both? Thanks in advance!