Yahoo email not working in Outlook is a very common problem. It happened to me and I thought it was going to be a big deal until I discovered that there are several different things that can cause the email program not to function correctly. Some of these things include an improperly set up email client or an incorrect file that needs to be deleted before the program can run properly. There is a simple way to fix this problem and get your email program running properly again.
First, you must do the basic level troubleshooting if you found Yahoo mail is not working with Outlook. So make sure that:
The device you are using to access the Outlook account must be connected to a stable internet that is giving adequate signal strength.
Also, check if your Yahoo account is suffering from an issue by opening a web browser, log into your Yahoo mail account, and send a mail to you. If you received the email, it means there is no issue with your Yahoo account.