Turns out, someone has injected a malicious script inside the HTML/PHP pages on my website. The code looks like this:
I have contacted my webhost about the script injection -- asking how it was done, and how to prevent future injections. No word yet from the webhost. In the meantime, I have removed all the rogue scripts. According to Google, I'm now supposed to create a Webmaster Tools account and submit a "review request" so that they can remove the big, red warning message.
I've heard very bad things about opening & using a Webmaster Tools account. There are various SEO's who claim that you should not use Webmaster Tools. My question: Will the message "This site may harm your computer" disappear on its own (over time), or am I required to open a Webmaster Tools account?