Is my account hacked?

Not necessarily. It often means Google was cautious about a new location, but check security activity to be sure.

Will this keep happening on my server?

Once you confirm the sign-in and use an app password or OAuth, it usually stops.

Gmail 534 5.7.14: please log in via your web browser

534 5.7.14Please log in via your web browserPermanent: retrying will not helpFrom Gmail and Google Workspace

Typical wording

534-5.7.14 Please log in via your web browser and then try again. Learn more at https://support.google.com/mail/answer/78754 - gsmtp

What it means

Google’s sign-in risk checks flagged the SMTP login. Rather than say the password is wrong, smtp.gmail.com answers 534 5.7.14 and usually includes a link to accounts.google.com, asking you to complete a browser sign-in. The wording typically reads like the example. In the IANA enhanced status code registry, 5.7.14 is named “trust relationship required”.

It shows up when an app signs in from an unfamiliar location, such as a cloud server in another country, or from an IP Google has seen abused. It is distinct from 5.7.8, where credentials are wrong, and 5.7.9, where an app password is needed.

Likely causes

A new server or VPS in a data center logging in to the account for the first time.
Logins from rapidly changing IPs, such as a mobile network or VPN.
Google suspecting the account is compromised after many failed attempts.
An app still using plain password sign-in that Google treats as risky.

How to fix it

Sign in to the account at mail.google.com from a trusted device and review the security alert; confirm it was you.
Check recent security activity for logins you do not recognise and change the password if needed.
Switch the app to OAuth or an app password with 2-Step Verification enabled, which avoids most risk challenges.
Retry the SMTP connection from the same server within a few minutes of confirming the alert.

Checks that apply

Your domain or sending IP (fills in the checks below)

SMTP Diagnostics Confirms connectivity and TLS to smtp.gmail.com so you can separate network trouble from sign-in blocks.
ASN Lookup Shows the network your sending IP belongs to, useful for seeing why Google treats it as unfamiliar.

FAQ

Is my account hacked?: Not necessarily. It often means Google was cautious about a new location, but check security activity to be sure.
Will this keep happening on my server?: Once you confirm the sign-in and use an app password or OAuth, it usually stops.

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