Short answer. Commerce Manager shows “HTML format isn't supported” when the URL you gave returns an HTML page rather than a data file; Meta accepts CSV, TSV, XLSX, XML (RSS or Atom) and Google Sheets. Open the URL in a private window: if you see a page, a login or an error message instead of a download, fix the URL or the server so the file itself is returned.
| Shown in Commerce Manager as | HTML format isn't supported |
|---|---|
| Effect | Whole feed blocked |
| Where to find it | Catalog → Products → a product’s Status and issues; feed-level errors under Catalog → Data sources → Download issue report |
| Free check | Not something a feed file shows; see below for what the check can tell you instead |
What Commerce Manager means by “HTML format isn't supported”
Meta’s data feed troubleshooting page puts it plainly: data files must be in XLSX, CSV, TSV, XML (RSS/ATOM) or Google Sheets format, and a file in any other format will not upload. “HTML format isn’t supported” is what you see when the URL handed back a web page. Meta did reach the address; what it found there was HTML.
The error is therefore almost never about your feed’s format and almost always about what the server served instead of the feed. Google-format XML is accepted; a page saying “not found” is not.
Why it happens
- A 404 or error page at the feed URL, served with a 200 status by a theme that styles errors.
- A store password or maintenance mode returning a login screen.
- A bot challenge from a CDN, which is an HTML page.
- A restricted Google Sheet, which returns Google’s sign-in page.
- A link to the storefront pasted where the feed URL should go.
How to fix it
In Shopify
Check the feed URL from your feed app in a private window. A storefront password returns the password page to Meta; remove it, or use the Facebook & Instagram channel’s own sync, which does not go through a URL.
In WooCommerce
Open the feed URL in a private window and look at what comes back. A WordPress 404 page means the feed route is not registered; a login page means maintenance mode or a members-only plugin; a Cloudflare interstitial means a bot rule. Our free plugin answers at its address without a permalink flush and marks its response as XML.
In a CSV or XML feed
Fetch the URL with a plain HTTP client and read the content type: it should be XML, CSV or text, not text/html. Fix the server so the file itself is returned with a 200, exclude the path from bot protection, and for Google Sheets set sharing to Anyone with the link and use the first tab.
How long until Commerce Manager clears it
On the next fetch that returns a data file. Re-upload from the feed’s Settings tab rather than waiting for the schedule, and resume the schedule if repeated failures paused it.
What FeedRobin does about it
This is the exact case the free feed check was taught to recognise after a visitor pasted a homepage: it reports “this address returned a web page, not a feed” instead of trying to parse HTML as XML. Run the check on the URL you gave Meta and it tells you in a sentence whether a feed is there.
Questions merchants ask
I uploaded a Google Shopping XML feed. Is XML supported?
Yes: Meta lists XML (RSS/ATOM) among its formats and reads Google’s XML as a file type. The error means the response was HTML, not that XML is wrong; usually the URL returned an error page or a login page.
Why does my feed URL return a page?
A rewrite rule that is missing so the pretty URL falls through to a 404 page, a store password or maintenance mode, a country block that serves a notice, or a bot challenge. Each returns HTML with a 200 or an error status, and Meta reports the format rather than the cause.
Does a Google Sheet count as HTML?
Not when shared correctly: Meta reads Google Sheets by URL, first tab only, with sharing set to Anyone with the link. A restricted sheet returns Google’s login page, which is HTML.
Sources
- Troubleshoot data feed errors in your catalog — Meta Business Help Centre
- Product data specifications for catalogs in Commerce Manager — Meta Business Help Centre