Troubleshooting Cloudflare managed challenge on Pure PortalTroubleshooting Cloudflare managed challenge on Pure Portal

Cloudflare uses a “managed challenge” page to verify that traffic is legitimate. In certain situations, users may get stuck on this page or be redirected repeatedly without ever reaching the portal. Cloudflare describes these behaviours here: “challenge looping,” “challenge solve issues,” and “stuck on challenge”. 

See more information from Cloudflare here:
https://developers.cloudflare.com/cloudflare-challenges/troubleshooting/challenge-solve-issues/

Below are the most common causes and steps to fix the problem:

1. Browser Extensions Blocking or Modifying the Challenge

Certain browser extensions interfere with Cloudflare’s challenge mechanism by blocking JavaScript, cookies, or the verification request.

Known extension that causes issues

• VisualSP – We have confirmed that VisualSP prevents some users from passing the Cloudflare challenge. Disabling VisualSP resolves the issue immediately in most cases.

What to do

1. Temporarily disable VisualSP (or similar productivity/security extensions).
2. Refresh the page and try accessing the portal again.
3. If it works, re-enable extensions one by one to identify the culprit.

2. Third-Party Script Blockers or Security Add-Ons

Extensions or software that block ads, trackers, pop-ups, or cross-site traffic may disrupt Cloudflare’s verification.

This includes:

• Ad blockers (uBlock Origin, AdBlock Plus, Ghostery)
• Privacy extensions (DuckDuckGo, Privacy Badger)
• Script blockers (NoScript)
• Local security software performing web filtering

What to do

1. Temporarily disable these tools for the Pure Portal domain only.
2. Ensure JavaScript is enabled in the browser.
3. Ensure cookies are not blocked.

3. Browser Cookies or Cache Causing Conflicts

Cloudflare relies on small verification cookies to allow access.

What to do

1. Clear cookies and browser cache for your Pure Portal domain.
2. Close all browser windows and try again.
3. Alternatively, test in an incognito/private window.

4. Using Out-of-Date Browsers

Older browsers may not support required security mechanisms.

What to do

Ensure you use an up-to-date version of:

• Chrome
• Edge
• Firefox
• Safari

5. Network or VPN Interference

Some corporate networks, VPNs, or proxies can:

• Modify requests,
• Block JavaScript calls,
• Or mask your IP in ways that Cloudflare considers suspicious.

What to do

• Try accessing the Pure Portal without VPN.
• Try from a different internet connection (home, mobile hotspot).
• Contact your IT department if you are behind a corporate proxy that might be rewriting traffic.

6. Still Stuck?

If you continue to experience looping or challenge failures:

• Take a screenshot of the challenge page (no need to include personal data),
• Note your browser version and installed extensions,
• Contact your institution’s support team or Elsevier Pure Support.

Including these details helps us diagnose whether the issue is caused by browser extensions, network filtering, or something else.