Yieldmanager / ad yieldmanager / edgesuite annoying popup very persistent

I hope someone can help me: Every time I go into any type of Yahoo mail

webmail account, I am getting continual security alert boxes popping up that

read as follows: " The current webpage is trying to open a site on the

internet. Do you want to allow this?

Current site: http://ad.yieldmanager.com

Internet site: http://content.yieldmanager.edgesuite.net

(click on) Yes  No

 

Each time I try to open an email message, click on

a folder, etc. etc. the box continues to pop up over and over again 

whether I click on Yes or No . I can't proceed unless I answer the

dialogue box to make it close. I have crashed my browser on

several occasions when the box was hiding behind other windows.

 

I called my internet provide because they make us

go thru Yahoo to use their webmail. The guy said it could be related to

NIS. I have also tried to adjust my IE 7 security/privacy settings with

no luck. I don't see either of these sites listed in the blocked sites

under IE privacy settings .

 

What in the world is "yieldmanager" ? Is that a tracking cookie?

I am willing to allow the thing if I could just get these dialogue boxes

to stop popping up in my Yahoo webmail accounts.

 

I'm not sure if this is related to any of the spyware blocking settings in

NIS - I have tried turning off various things to see if the problem will

resolve that way, but again, no luck.

 

Any help would be much appreciated.

 

 

Cathy