I was asked recently, if emailing to clients with  correctly configured landing pages but if you get spam reported, can this blacklist your site from search engines.

I;d imagine it'd have to be very substantial. I've never come across this before. I believe that SEO and email marketing are apart. For example if you gmail blacklisted, well that's it. It's not the entire Google will blacklist you for having some spam complaints.

I'd like to know if anyone has ever heard of this as if so, using applications like Send to my friends, or forward to a friend etc, needs to be treated very cafefully.

My gut reaction is this is a myth, but one I've not come across to date and I'd love to find out more!

Thanks!