In Chrome on a client computer, each time she'd open a window, you could see the browser looking to the site mnh.winnermore.info for content. This included when she'd click to reply to a message within her Exchange webmail. There was no program in add/remove programs. There were no extensions in Chrome. Malwarebytes, rkill, adwcleaner, and all other cleaners I use found nothing.
This problem persisted in even a new Chrome user profile (same Windows profile). I even searched through the registry and found nothing. Eventually, I came across this site:
Per the page above, the fix was to set Chome to default settings. This worked. I don't know how/why, but somehow this site embeds itself somewhere I couldn't find it at all.