Public LinkedIn profile url returns server Status code 999

Question

LinkedIn Consumer Support asked me to add this question here for #LinkedIn developpers to answer this.

I have seen there are multiple questions about this 999 status code, but they are all API related. My question is not API related.

Here it is. On my website I have a link to my public LinkedIn profile: https://nl.linkedin.com/in/jpcornelissen/nl The broken link checker plugin on my website tells me that this link is broken with the error: SERVER RESPONSE: HTTP/1.1 999 Request denied

Why is that? The page is accessible so it should return status code 200 not 999. Status 999 is not even an existing http status code.

The issue is not plugin related. You also get the 999 status code if you check with http://tools.seobook.com/server-header-checker/

Regards

Answer 1

Maybe you can find the answer here : 999 Error Code on HEAD request to LinkedIn or here : https://social.msdn.microsoft.com/Forums/vstudio/en-US/5a4f8eb5-bf1b-4776-b4bb-4baef621838f/999-non-standard-linked-in-error?forum=csharpgeneral

It seems that LinkedIn blocks "bad" request with this 999 non-standard Status Code (they should better respond with 400 Bad Request and an explanation). Some reports that it comes from the HEAD method (which is similar to GET but does not request the body), or a missing header( Accept-Encoding), or the User-Agent header, or the source IP (from Heroku).

Only LinkedIn can explain why. Chances are they will not explain why because of Security through obscurity .

Answer 2

Update,

It looks like this is a common occurrence and my investigation concluded when I realized the resource wasn't available for the main LinkedIn servers. Thus, when inspecting the profile badges page the script we need also has a status code of 999. I've opened a ticket, hopefully in the future they will provide a more stable means with full html+css options :)