A number of the newer Malware "suites" are having such issues.. CA may have a patch for your issue. Although their knowledgebase is extensive, the patches below appears to apply:
I cannot surf the Internet since installing CA Personal Firewall
I have very slow browsing with Internet Explorer after Installing CA Personal Firewall on Windows Vista
Hope this helps.
Grif
Operating System: Windows Vista Home Premium
Purchase Date: August 2007
Hi everyone,
I recently installed a copy of the CA Internet Security Suite 2007 on my laptop. Almost immediately after I installed the product, my Internet connection became sporadic. I have a wireless Internet connection. I've tried adjusting the settings and figured out that my firewall was the problem; I changed the setting for explorer.exe to "allow" and that gave me a limited Internet connection, but even that expired. The only way I can get my Internet to work now is by disabling my firewall, and with the firewall disabled the Internet does not run as quickly as it used to. Does anybody have any experience with these types of issues?
Thanks!

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