What the bounce says
Exact wording as it appears in the rejection or NDR. Placeholders such as x.x.x.x and example.com stand for your own address and domain.
550-5.2.1 The email account that you tried to reach is disabled. Learn more at https://support.google.com/mail/?p=DisabledUser 550-5.2.1 The user you are trying to contact is receiving mail at a rate that prevents additional messages from being delivered. Please resend your message at a later time.
Gmail uses 5.2.1 for two different situations. One text says the recipient account is disabled; the other says the recipient is receiving mail faster than Gmail permits. The first is permanent from your perspective; the second clears on its own.
Most common causes
- The recipient account was disabled or suspended
- The recipient is being flooded and Gmail is protecting the mailbox
- The recipient is a Workspace user whose account was suspended by an administrator
What to verify next
- Read which 5.2.1 variant appeared — disabled versus rate
- For a disabled account, contact the recipient another way
- For the rate variant, retry later and reduce volume to that recipient
- Remove disabled addresses from lists
Disabled account
Google suspended the account, the user disabled it, or a Workspace administrator suspended the user. Mail is refused rather than queued. Remove the address from lists and contact the person another way.
- Disabled: permanent until the account is restored.
- Rate variant: temporary, protects the recipient.
- Read which text appeared.
Receiving-rate variant
Gmail limits how much mail one mailbox can accept in a short period to protect it from floods. If you are sending many messages to one recipient — notifications, alerts, a mail loop — Gmail pushes back. Reduce the rate to that recipient and let the queue retry.
A sudden appearance of this variant often reveals a loop or a runaway alert system.
Confirm on the sending side
Check how many messages went to that recipient in the last hour. If the number is high, fix the source before anything else.
Best diagnostic path
Mail Failure Doctor
Classify the complete rejection and preserve provider-specific diagnostic context.
Open analysis → Live analysisEmail Infrastructure Digital Twin
Map the domain’s public mail infrastructure and provider relationships before remediation.
Open analysis →Known limits
- Gmail does not say why an account was disabled.
- Receiving-rate limits are not published.
Common questions
Can I get the account re-enabled?
Only the account owner or, for Workspace, their administrator can.
How fast is too fast for one recipient?
Gmail does not publish it. Dozens of messages in minutes to one address is enough.
Is the rate variant a spam judgement?
No. It protects the mailbox. It becomes a reputation problem only if it continues.
Why the exact message matters
The same status family can be triggered by different conditions, and providers frequently add diagnostic text that narrows the issue. Use the complete rejection text rather than treating the numeric code as a complete diagnosis.
Provider reference
For the provider-defined meaning and current requirements, review Gmail SMTP errors and codes.