An unknown error has occurred. (error code 1)
In short
Code 1 is Meta's catch-all "unknown" error: something failed on Meta's side without a specific reason, and Meta describes it as possibly a temporary issue.
By Mathieu Malige, founder of Apogee
· Checked on 8 October 2026
Exact message
| Field | English | French |
|---|---|---|
| Message | An unknown error has occurred. | not captured yet |
| Description of code 1 (Marketing API error reference) | An unknown error occurred. | Une erreur inconnue s’est produite. |
Where it shows up: in the response of Meta's Marketing API when an ad, ad set or creative is created, for example by a tool that launches ads for you.
Why it happens
- Code 1 means “API Unknown”. Meta’s Graph API documentation describes it as possibly a temporary issue due to downtime: wait and retry. If it happens again, check that you are requesting an existing API.
- Meta’s Marketing API error reference describes code 1 as “An unknown error occurred.”, with no further detail.
- No setting is named, so the message does not tell you what to change in the ad.
How to fix it
- Check what was already created before retrying (in Ads Manager, the Campaigns, Ad sets and Ads tabs) to avoid duplicates.
- Wait a few minutes and repeat the same action.
- If it keeps failing, go through the checks Meta’s help center gives for “something went wrong” errors during ad creation (error 1487470): your account status in Business Support Home, outages on the Meta status page, your browser’s cache and cookies, then duplicating the ad.
- If you use the API, keep the
fbtrace_idof the failed call for Meta support.
How to avoid it next time
- On the API, retry code 1 after a delay and stop after a few attempts.
- Also read the
error_user_titleanderror_user_msgfields of the response when they are present: they are the texts Meta writes for the user, in the language of the request.
Frequently asked questions
Is error code 1 my fault?
Usually not. Meta describes it as possibly a temporary issue due to downtime.
How many times should I retry?
Meta does not give a number. Retry a few times with a pause; if it persists, Meta advises checking that you are requesting an existing API.
What should I send to Meta support?
For API calls, the fbtrace_id returned with the error; Meta's documentation says it helps them find the logs, but it expires shortly.
Related errors
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