Why do I keep getting this message on Google??

My browser homepage is set to www.google.com. But when I launch Firefox, I get the following message:

We're sorry...

... but your query looks similar to automated requests from a computer virus or spyware application. To protect our users, we can't process your request right now.

We'll restore your access as quickly as possible, so try again soon. In the meantime, if you suspect that your computer or network has been infected, you might want to run a virus checker or spyware remover to make sure that your systems are free of viruses and other spurious software.

If you're continually receiving this error, you may be able to resolve the problem by deleting your Google cookie and revisiting Google. For browser-specific instructions, please consult your browser's online support center.

We apologize for the inconvenience, and hope we'll see you again on Google.

How can I prevent this????

Why do I keep getting this message on Google??antivirus download

Its your proxy you are going through. Google thinks you are trying to go through google to hack a site (based of the IP address you are internet is coming from). You either have to change the proxy, or just deal with it. (keep trying to do it).

Why do I keep getting this message on Google??bmw

"If you're continually receiving this error, you may be able to resolve the problem by deleting your Google cookie and revisiting Google. For browser-specific instructions, please consult your browser's online support center."

What part of this don't you understand? Delete your Google Cookie and re-start your browser. Done.