Try this before u think of Installing any Firewall or even switching the Read software it self
Launch the adobe software !!! In your case the Adobe Reader... now in the menu bar Click
Help, and then
Check for update...
now make sure u have connection to the Internet and no firewall is blocking the software, so u should see the software / in u case the reader is checking for updates
as it completes the check, it should present this window in front of u
Click the option
Preference in that window !!!
Now please check off the option which says
Autometically Check for Adobe updates
Click oK.. then close the Window... so from now on Adobe softwares will not check for updates unless u manually check