You probably think that this is a misbehaving crawler problem but this CloudFlare website:
- Blocks Internet Explorer on Windows 10 desktop (uses Windows API for HTTP)
- Allows Edge on Windows 10 desktop (uses Windows API for HTTP?)
- Blocks my crawler on Windows using WinInet Windows API for HTTP
- Allows my crawler on Mac using Mac API for HTTP
Accordingly to this Internet Explorer 7 on Windows Vista should be support on even free CloudFlare: https://support.cloudflare.com/hc/en-us/articles/203041594-Cloudflare-SSL-cipher-browser-and-protocol-support
I am in preliminary research phase, but it feels like a certificate issue. I have not experienced this problem before on any website when using Windows 10. (But yes, older versions of Windows can have similar problems to certificate problems)
Any ideas? I have not implemeted HTTP2 part of Windows API - is that a possible explanation? Would just be a bit odd to require that so.... But could possibly explain why Edge and not IE works.