PROTECT YOUR SERVER: A new Internet study reports that fewer than 1 percent of all public Web servers can handle secure transactions. But even if you don't care about actually taking credit card numbers via the Net, your site may still be vulnerable to Web vandalism, graffiti or other attack. Particularly vulnerable are certain types of login configurations. Protecting your site involves issues more technical than most marketers care to handle, so it's crucial to check with your developer and Web hosting firm to make sure they're taking proper precautions. Don't assume it's already taken care of, because often, it's not.