Carol,
I have not heard of this happening. You might want to log into Yahoo Groups, and click on "My Account". When that page comes up, scroll down to the link that says "Edit your marketing preferences." Go through it and make sure you unclick all the boxes so they won't be marketing anything to you. I'm not sure if that would make a difference with the pop ups but it's what came to mind.

A lot of people have pop-up blockers on their computers, you might want to look into that.

HOpe that helps,
Kitty