How to Fix Cloudflare Error 520 | HTTP 520
WhenyourCloudflareserverreceivesaninvalidconnectionrequestsobungledthatitcan’tevenclassifytheissue,itreturnstheannoyinglyvagueError520:WebServerIsReturningAnUnknownError.Notimetospare?Clickhere[1]tojumptostraighttohowtofixthiserror.WhatisCloudflareError520:WebServerisReturningAnUnknownError?CloudflareError520isaserver-sidediagnosticmessageindicatingthateventhougharequestreachedtheoriginwebserver,theserverreceivedaninvalidHTTPresponseordidn’tknowhowtointerprettherequestatallandwasunabletoproc...
When your Cloudflare server receives an invalid connection request so bungled that it can’t even classify the issue, it returns the annoyingly vague Error 520: Web Server Is Returning An Unknown Error.
No time to spare? Click here[1] to jump to straight to how to fix this error.
What is Cloudflare Error 520: Web Server is Returning An Unknown Error?Cloudflare Error 520 is a server-side diagnostic message indicating that even though a request reached the origin web server, the server received an invalid HTTP response or didn’t know how to interpret the request at all and was unable to proceed.
The most common causes for this are either a program or system task that was running out of resources and needed to be terminated, or the server was overloaded.
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