Last Updated: 11 Jun 2020 10:20 by ADMIN
Created on: 23 May 2020 09:56
Type: Bug Report
How Can I Capture "Warning: ClientHello record was 514 bytes long. Some servers have problems with ClientHello's greater than 255 bytes" by Fiddler?
Hi, I'm trying to capture the iCloud Create info Page from Fiddler,  But it's always get error. How  Can I slove it? Can you help me?
Posted on: 10 Jun 2020 15:56

The message about the length of the ClientHello isn't causing this problem (and should probably be removed, because almost every middlebox that had a problem with long ClientHello messages was fixed over 5 years ago).

The problem you're encountering is almost certainly caused by the fact that Apple is using Certificate Pinning for the server. See

Nick Iliev
Posted on: 29 May 2020 08:59



Can you confirm that you have followed the steps required to enable capturing traffic from an iOS device? See the related documentation here. Alternatively, check if you are facing this issue related to different versions of TLS. In the very same thread, you will also find that some applications are using an extra layer of security through certificate pinning (see details here).

If your issue still persist, you could send us the exact steps you are taking so that we could reproduce the issue.


Nick Iliev
Progress Telerik

Progress is here for your business, like always. Read more about the measures we are taking to ensure business continuity and help fight the COVID-19 pandemic.
Our thoughts here at Progress are with those affected by the outbreak.