Cloudflare captcha challenge

Hello, I need an advise from the experts.

For the past 2 months we have been receiving captcha challenges when browsing multiple websites at work. It’s only happening on the company’s network and for all users. Since we are behind a SonicWall firewall, I already contacted SonicWall support, they ran a few tools to see if there was an issue that could cause this, we also captured multiple packets to analyze if a computer within the network was the issue, but all the tests were fine, there were no red flags. I also contacted the our ISP and asked them to check if maybe our static IP was blacklisted and their reports came negative, our IP address has no issues. Just to double check, I confirmed this information using MX toolbox. We have scan all of our PCs for malware and all are clean. We also change our preferred dns to point to google’s just to test and the issue didn’t resolve.

Any advise on what should I check to try to resolve this?
Thanks in advanced.

1 Like

I’m betting you have a static address, or range of addresses. In cases like these, I wonder if there’s a way for your ISP to contact Cloudflare directly. @cloonan?


Hi, @user899 the best way to contact Support is for both you and the ISP to make contact. If you open a ticket, ask the ISP to reference that ticket number when they mail support AT cloudflare DOT com.

Please share your ticket number here so that I can track them.


Thanks for the information. Because we are getting captcha challenges on multiple websites and from different services, I’m not sure if this issue only pertains to cloudflare. Please see snapshots attached. Should we still contact Cloudflare and open up a ticket?

Hi sdayman, you are correct, we have a static address and bought a range of addresses too. What’s weird is that last week we switched the static IP to a different from the range of IPs we were given by our ISP and the captcha challenges went away for about 3 days. After the 3rd day they reappear. As I stated we reach out to the ISP and they told me that on their end the IP is whitelisted and have no issues.

I still think you should open a ticket. I don’t get challenges when I visit those two sites. And considering that you changed static addresses which was good for a few days, then it happened again…something’s up that you and your ISP can’t pin down. Only Cloudflare knows why you’re getting challenged. It could be something as simple as a rate limit, or someone/something on your network doing naughty things.

1 Like

Hi Sdayman.

Thank you. I just submitted a ticket (1988992), hopefully I can hear back from them. :slight_smile:

1 Like

This topic was automatically closed after 30 days. New replies are no longer allowed.