Why is my email not working and has pop up saying sign in failed

[AC Question]

I have not been able to send or receive emails for a proxy 48 hours

 

[Tim1954]

Do you have internet access? Can you google stuff? If yes, try settings... Gmail (or whatever email client you're using)... Wipe the app cache, force stop the app itself and try again. If still no luck, you may have to uninstall and reinstall the app... If all that fails, come back and tell us so we can troubleshoot more...

 

[ManiacJoe]

What phone?
Which version of android?
Which carrier?
Which email app?
Which email provider? Yahoo?

 

[B. Diddy]

Welcome to Android Central! Are you using Yahoo Mail?