Google has detected harmful content

I ask about this awhile back and didn't really get an answer that helped. I did go to google and requested they remove it but it keeps coming back and now it's happening on most the domains on my smartermail server. I'm thinking google is seeing something in Smartermail it doesn't like and Smartermail needs to work on this so it doesn't happen but I may be way off base.

When I reply to an email I get alerts from Google Chrome. When I login to my google account and check my Security Issues I get this.

Google has detected harmful content on some of your site’s pages. We recommend that you remove it as soon as possible. Until then, browsers such as Google Chrome will display a warning when users visit or download certain files from your site.