While using the services of Yahoo, sometime user encounters the error message like “Unable to process your request--- error 999”. Primary reason of this error is Yahoo bandwidth and it can be resolved easily. One needs to have good technical knowledge to fix this error. So, if you or any of your friends have noticed this error then it is recommended not try your hands if you are not an advance computer user or well versed with Yahoo technical aspects. For you immediate Yahoo customer service available for severely irresolvable issue is there. Just dial the toll free number and get free assistance.