Removing advertisements from yahoo messenger

1. Close the messenger,
2. download the Self Extracting file noadsse.exe - 64KB
3. run noads.exe. from it.
4. Restart Messenger…simple !!

AlternativelyNice info also found here.
If you install new versions of Yahoo Messenger, you’ll have to repeat the steps above, as Yahoo setup rewrites the registry entries. New versions will most likely make removing the ads more difficult or even impossible.