T Mobile Message Log Why Does Intellisync For Yahoo Stop Working-can't Log On-after Using Syncml For Mobile Phone?

Why does Intellisync for Yahoo stop working-can't log on-after using syncml for mobile phone? - t mobile message log

I have successfully synchronize Intellisync for Yahoo Microsoft Outlook calendar with Yahoo. After activated and synced with my Motorola V400 mobile phone with Yahoo, which now gets the message "You can use a can not connect to Yahoo, username and password and try again" when trying to use Intellisync. I have a sub account and started over. Intellisync has worked well until the sub-account with the phone after that I get the same error synchronized. If I would choose a better service to Intellisync. Someone knows how can I retrieve it?