Growl
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I have ClamXav as my virus checker.
All fine until about a week ago. Now I keep getting messages/pop-ups (?) urging me to install Growl. Usually this occurs when using Safari but sometimes just at random or when moving a folder from my desktop into one of my own filing places.
The messages warn me perhaps that the folder wasn't scanned, or that I might wish to remove the ClamXav "Sentry". This last idea concerns me.
I have been on the Growl web-site but am no wiser about its credentials. Is Growl "above board", and why do I need it?