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I see the error 412 Precondition failed with the below code. It used to work until 1st of April 2021. It started failing from 2nd April 2021.

var response = new WebClient().DownloadString("http://www.dce.com.cn");
Please can someone help me with this?
Thanks in advance
                Seemingly dce.com.cn changed something. Perhaps they check the User-Agent header now. Perhaps it's something else.
– ProgrammingLlama
                Apr 9, 2021 at 5:55
                Weirdly this works from the browser. Only doesn't work from c# code. I captured the request from fiddler. Tried the same request headers from c# as well. Still seeing the same 412 error.
– user965291
                Apr 9, 2021 at 8:21
                *** Fiddler Request ***  POST dce.com.cn/publicweb/quotesdata/dayQuotesEn.html HTTP/1.1 Connection: keep-alive Content-Length: 69 Cache-Control: max-age=0 Upgrade-Insecure-Requests: 1 Content-Type: application/x-www-form-urlencoded User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.90 Safari/537.36 Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,/;q=0.8,application/signed-exchange;v=b3;q=0.9 Accept-Encoding: gzip, deflate Accept-Language: en-US,en;q=0.9
– user965291
                Apr 9, 2021 at 8:26
                Yes @Julian-Reschke. The actual URI we use is in the fiddler request. To make it simple initially I provided the base URI.
– user965291
                Apr 9, 2021 at 12:20
        
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