Package with mismatched tag symbolizing wrong file format
When a download should be a PDF, CSV, ZIP, or DOCX—but Chrome saves it as .txt or “Unknown”—the problem is usually one of three things: the site sent the wrong file type, Chrome intercepted it, or your device is opening it with the wrong app.

Here’s a quick if/then decision tree first, then the deeper steps.

Quick decision tree (start here)

  • If the file name ends with .txt → go to 1 (site response + “Open in browser” behavior).
  • If the file has no extension (or says “Unknown”) → go to 2 (server headers + Content-Type).
  • If the extension is correct but it opens in the wrong app → go to 3 (Windows/macOS default app association).
  • If it only breaks on one website → do 1 and 4 (extensions + site settings).
  • If it breaks on every website → do 5 (Chrome download settings + profile health).

1. If Chrome is “saving the page” instead of downloading the file

Sometimes you’re not actually downloading the file—you’re downloading what the site rendered (an HTML view), and Chrome saves it as text or a page.

File being saved into a folder via an arrow

  • Try a direct download action: look for a button labeled Download/Export, not a preview link.
  • Right-click the link → choose Save link as (this often bypasses a viewer page).
  • Open the link in a new tab: if it shows a preview (PDF/image/doc viewer), look for the viewer’s own download icon.
  • Check if you’re getting a login page: if you’re signed out or your session expired, the “download” may actually be an HTML sign-in page saved as .txt/.html.

If the downloaded file’s content looks like web page code (lots of angle brackets), it’s almost always “saved HTML,” not the real file.

2. If the file has no extension (or shows as “Unknown”)

This usually means the website didn’t tell the browser what it’s sending (missing/incorrect Content-Type or Content-Disposition headers), so Chrome can’t label it.

  • Download the same file in an Incognito window. If it works there, something in your regular profile (extension/cookie state) is interfering.
  • Try the same download in another browser (Edge/Firefox). If every browser shows “Unknown,” it’s likely the site/server.
  • Try a different network (mobile hotspot). Some corporate networks/security tools rewrite downloads and strip headers.

When it’s a server-header issue, there isn’t a “Chrome setting” that can reliably fix it—you typically need the site to correct how it serves the file.

3. If the extension is correct, but it opens as text anyway

This is usually your device’s file association, not the download itself: the file is fine, but it’s being opened by a text editor.

One file routed to two different app icons

  • Don’t judge by the icon: confirm the filename ends with the expected extension (like .pdf, .zip, .csv).
  • Windows: right-click the file → Open with → choose the correct app → check Always if you want to keep it.
  • macOS: select the file in Finder → Get Info → Open with → choose app → Change All.
  • If it’s a CSV: opening in a text editor is “normal,” but you may want Excel/Numbers/Sheets. The file isn’t broken—just opened differently.

If the file extension is missing, add it only when you’re sure of the type (for example, a ZIP should start downloading as a compressed archive; a PDF usually opens as a PDF preview in many browsers).

4. If it happens on one site only: check extensions, site settings, and content blockers

Download flows often use redirects, cookie checks, or a JavaScript-generated link. Extensions that modify headers, block scripts, or scan downloads can break that handshake.

  • Disable extensions temporarily (especially ad blockers, privacy blockers, download managers, “security” scanners) and try again.
  • Check site permissions: Chrome Settings → Privacy and security → Site settings. Look for anything you’ve blocked for that site (pop-ups/redirects can matter for download flows).
  • Clear site data for just that site (cookies/cache for one domain), then sign in again and retry the download.

A good tell: if Incognito works but normal mode doesn’t, it’s almost always extensions or stored site data.

5. If it happens everywhere: reset download behavior (without nuking everything)

When every download starts acting strange, focus on Chrome’s download handling and profile health.

  • Check where files are saving: Chrome Settings → Downloads. Ensure you can write to that folder and it isn’t a synced/locked location.
  • Turn off “Open certain file types automatically”: in Chrome’s Downloads page, if you previously set a file type to auto-open, remove that setting (look for an “Always open files of this type” toggle from the file’s context menu).
  • Update Chrome: outdated builds can have odd MIME handling bugs with certain sites.
  • Try a new Chrome profile: if downloads are normal in a fresh profile, your main profile likely has a setting/extension/corruption issue.

If you’re on a managed device (work/school), policy settings can also control downloads and file handling. In that case, the “fix” may require your admin.

Final thoughts

Most “download became .txt/Unknown” cases come down to: you saved a preview page, the site sent the wrong headers, or your device opened the file with the wrong default app.

If you narrow it to “only this one site, in every browser,” it’s reasonable to stop troubleshooting locally and report it to the site—include the exact filename you expected and what you received.