i keep getting "The sender address was invalid" when trying to reply to an email.

Remove your email account and set it up again

Make sure that all of your emails are there or make sure that your email is saved somewhere other than your device. On your device, go to Settings > Mail, then tap Accounts. Tap the email account that you want to remove. Tap Delete Account.

If you can't receive email on your iPhone, iPad, or iPod touch ...

If you can't send an email on your iPhone, iPad or iPod touch

1. When you make an iOS or iPadOS backup in iCloud or iTunes, it backs up your mail settings, but not your email. ... 
2. Make sure your device is connected to the Internet.
3. Check with your email service provider to find out if there's a service outage.

More items...•

If you can't send an email on your iPhone, iPad or iPod touch ...

Which email account are you referring to? Google, iCloud, AOL, Exchange, Outlook, Yahoo or any Other (Refer to the pic )below

1. Is this your corporate iPhone? Then please contact the system administrator of your corporate
2. If it is your personal device, in that case, do you have any profile installed by your corporate/organisation/enterprise/School Management?
   1. Erase the profile added by you If you have installed a profile on your own --> Install or remove configuration profiles on iPhone - Apple ...
   2. Or please contact the system administrator of the organisation who provided the profile to you

granthewitson Said:

"i keep getting 'The sender address was invalid' when trying to reply to an email.: I receive a email from friends and need to reply but I get 'the sender address is invalid'. This happens to many of my contacts who I try to respond to. Iphone 12 and the latest IOS update. There is no 'mail' item in the settings menu but I do have the mail app and can receive emails."

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Troubleshooting iPhone eMail:

A. Start Here: If you can't Send or Receive eMails on your iPhone - Apple Support

B. Disable All VPNs:

Are you using a VPN? If so, disable it. Security Software just gets on the way on an Apple Device, and this is a put example of how and why.

C. Use of an App Password:

You may need to use a new app password. If you are using different devices, then you need one for each device. So, contact your eMail provider to find out how to get an App Password. As an example, for AOL Mail, Go Here: Create and Manage Third-Party App Passwords - AOL Help

D. Add the Account Back:

If you remove the account, then you would be able to add it back, perhaps fixing all sync errors.

E. Report this to Apple:

Do your Part: Provide Apple with feedback on this, letting them know about this issue.  Apple may not get back to you directly, but the more feedback they receive on this, the more they will know what is occurring, and what bug fixes to include in updates to come. Apple will know nothing of this, if you don't report it to them.

1. Go Here: Feedback - iPhone - Apple
2. Select: "Bug Report" for the "Feedback Type"
3. Comment: that this all began after installing an update. Include the URL of this thread.
4. Proceed from there as necessary