I have been using Vista Home Premium and Zonealarm free for my Firewall. Usually Windows Security Centre monitors and says I'm fine as Zonealarm is working properly. For the last couple of days, even though Zonealarm is working correctly I get a balloon come up and say there is no firewall for my computer and to switch on Windows Firewall. I do this but Zonealarm turns this off as it is a second firewall. I don't know why security centre has stopping monitoring Zonealarm for me as I have not changed any settings at all.
When I say I will use alternative firewall, it asks if I want security centre to monitor it but then it just gives me the windows firewall option and not zonealarm.
Does anyone have any ideas how I can get Security Centre to monitor Zonealarm again for me or is just a case of telling the centre I'll monitor my firewall myself?
I tried what you suggested but nothing was found at all on my computer with the Malwarebytes program.
However, I have just downloaded and installed a more up to date version of Zonealarm compared to the one I had installed and this has worked. Windows Security Center is now recognising Zonealarm free has my firewall and is not telling me that I don't have a firewall running.