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Third-party cookies blocked in WebTrader platforms

Login, a payment step or an embedded part of the platform fails, while the rest of the site works normally.

WebTrader platformsThird-party cookies blockedbrowsercookies

What is causing it

Your browser is blocking cookies from addresses other than the one in the address bar, and part of the platform is served from a second address.

Why this happens

Many platforms handle sign-in, charting or payments on a different address from the main interface. When the browser refuses to store cookies for that second address, the piece it powers fails while everything else behaves. Browsers have been tightening these defaults for years, which is why a platform that worked for months can break after a browser update.

The fix, step by step

  1. Add an exception for the platform's address in your browser's cookie or tracking settings rather than turning protection off globally.
  2. If your browser offers a shield or protection toggle in the address bar, switch it off for this site and reload.
  3. Test in a private window, remembering that many browsers block third-party cookies there by default, so failure in private and success normally points at this setting.
  4. If your provider names a second address for sign-in, allow cookies for that address too.
  5. Try a different browser to confirm the behaviour, since defaults differ between browsers and change between versions.
  6. Ask your provider whether their platform requires third-party cookies before changing more settings than you need to.

How to confirm it is fixed

The failing step completes, and still works after closing and reopening the browser.

Stopping it happening again

Add the exception in the browser profile you trade in, and re-check after major browser updates, which sometimes reset such exceptions.

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Still stuck? Some issues are specific to your broker or your app version, and their support desk can confirm server names, account status and outages. See all WebTrader platforms problems or the full help hub.