Some users are using bit.ly links in their signatures and it causes anyone loading the page with your signature to either not be able to view it or to bypass the warning.
To bypass, you can do this:
Please do not include bit.ly links in your signature. If you need more characters for your signature please contact me and I'll see if I can have it done.When you get the "the site head contains malware" warning click on the Details link on that page.
Here you need to click on "visit this unsafe site" link to visit the site in question.
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Bypassing the warning can put your computer at risk. It is highly recommended to have some form of protection in place including up to date antivirus software but also browser specific security extensions such as NoScript to block these kind of attacks from affecting your computer.
Update: Google has now updated and fixed the problem. Bit.ly is looking in to the malicious sites that put them on the automated safebrowsing list.
