If your email stopped sending after you changed your password, the password change may not have fully reached every place that sends mail.
This is common. Your mailbox password may be correct, but Outlook, your phone, your tablet, or your mail app might still be trying to send using old saved credentials.
You may be able to receive emails, but sending fails. Or Outlook might keep asking for the password again and again, even after you enter the new one.
When I work on this kind of problem, the goal is simple. Find where the old sign-in details are still being used, then update or reset the affected account properly.
If your email is not sending and you are not sure whether the problem is the password, Outlook, your phone, or the mail server, see my main emails not sending page.
Why Email Can Stop Sending After a Password Change
Email apps often store separate settings for receiving and sending mail.
That means changing the password in one place may not update everything.
For example, the app may receive mail using the new password, but still try to send through the outgoing mail server using the old saved password.
This is one reason people often see messages like:
- 🔐 Outlook keeps asking for password
- 📤 SMTP authentication failed
- ⚠️ Sign-in required
- 🔁 Enter password loops
- 🚫 Message could not be sent
The password itself may be fine. The problem is often that the mail app is not using the right authentication method anymore.
Old Saved Credentials Can Keep Breaking Sending
One of the most common causes is an old password saved somewhere on the device.
This can happen in Outlook, Windows Credential Manager, Apple Mail, iPhone mail settings, Android mail settings, or inside the browser profile used to sign in.
The confusing part is that repeatedly typing the correct password does not always fix it.
If the old credential is cached, the app may keep retrying the wrong saved sign-in details in the background.
In Outlook, this can look like a password prompt that keeps coming back even though the password is correct.
If this is mainly happening in Outlook, my article on Outlook not sending emails but receiving works explains the Outlook-specific side of this problem.
App Passwords May Be Required
Some email accounts no longer allow a normal password to be used in older mail apps.
This is especially common when two-factor authentication is turned on.
Instead of using the main account password, the account may require an app password for Outlook, Thunderbird, Apple Mail, or another mail client.
This can cause problems after a password change because the old app password may be revoked, expired, or no longer accepted.
In that situation, entering the new normal account password into Outlook may still fail.
The fix is not always to keep retyping the password. The correct fix may be to create a new app password, remove the old saved details, then update the mail app with the new generated password.
Two-Factor Authentication Can Change the Rules
Two-factor authentication is a good security feature, but it can change how email apps are allowed to connect.
After a password change, the account provider may require a fresh sign-in, security approval, or app-specific password before sending works again.
This can affect:
- 📧 Outlook on Windows
- 💻 New Outlook or classic Outlook
- 📱 iPhone and Android mail apps
- 🌐 Gmail, Microsoft 365, Yahoo, iCloud, and hosted business email
- 🏢 Business email accounts using custom domains
This is why the same mailbox might work in webmail, but fail in Outlook or on a phone.
SMTP Authentication Failed Usually Points to Sending Settings
If you see an SMTP authentication error, the receiving side of the mailbox may not be the real problem.
This is one reason you may be able to receive emails but can’t send.
SMTP is the outgoing mail service. It is what your email app uses when it sends messages.
After a password change, SMTP can fail because:
- 🔑 The outgoing server still has the old password saved
- 🔐 The account now requires an app password
- 🧩 The authentication method is no longer accepted
- ⚙️ The outgoing server settings are incomplete or incorrect
- 🚦 The provider has temporarily blocked sign-ins after suspicious activity
This is why guessing settings can waste time. The sending path needs to be checked properly.
Sign-In Required Loops Can Be a Token Problem
Modern email accounts often use sign-in tokens rather than only storing a simple password.
When the password changes, those tokens may become invalid.
The mail app may then get stuck in a sign-in loop. It asks you to sign in, appears to accept the password, then asks again later.
In some cases, the account needs to be removed and added again so the app can create a clean, current sign-in connection.
This needs to be done carefully, especially with business email or older POP accounts, because removing an account without checking the data first can risk losing locally stored mail.
Why Webmail Might Still Work
A useful test is whether you can send from webmail.
If webmail works, the email account itself is probably active and the password is probably correct.
That does not automatically mean Outlook, your phone, or your other mail app is configured correctly.
It usually narrows the problem to the device, app, saved credentials, authentication method, or outgoing server settings.
If webmail also fails, the issue may be with the account, provider, password reset, security lock, or mailbox service itself.
What I Check When Fixing This
For this type of job, I usually work through the problem in a controlled order instead of randomly changing settings.
- ✅ Confirm the new password works in webmail
- ✅ Check whether the problem affects sending only, or both sending and receiving
- ✅ Check Outlook, phone, tablet, and other mail apps separately
- ✅ Remove outdated saved credentials where needed
- ✅ Check whether two-factor authentication or app passwords are required
- ✅ Verify outgoing SMTP settings and authentication
- ✅ Re-add or repair the account only when it is safe to do so
The right fix depends on the account type and the mail app being used.
Be Careful Before Removing the Account
Removing and re-adding an email account can be a valid fix, but it is not always the first thing to do.
Before removing an account, it is important to know whether the mail is safely stored on the server.
With IMAP, Microsoft 365, Gmail, and many modern setups, mail is usually synced from the server.
With older POP setups, some mail may exist only on the computer. Removing the account without checking first can cause avoidable data loss.
This is especially important for older Outlook installations and long-running business email setups.
When to Get Help
It is worth getting help if you have already changed the password and the email still will not send, Outlook keeps asking for the password, or you are seeing SMTP authentication failed messages.
These problems can usually be fixed quickly, but the right fix depends on where the authentication is failing.
PcRiot helps home users and small businesses in Perth with email sending problems, Outlook password prompts, app password setup, and account sign-in issues.
If your email stopped sending after a password change, contact PcRiot and I can help identify whether the issue is with the account, the app, the device, or the outgoing mail server.