![cannot connect to the zcs upstream server cannot connect to the zcs upstream server](https://linoxide.com/wp-content/uploads/2016/08/33.zimbra_mailbox_login.png)
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However, sometimes, on a rare occasion the problem could lie locally with your browser, an issue with your home networking equipment, or something else that could lie with your control.
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What you can ascertain straight away, however, is that a 502 error is related to a communication problem between a gateway or proxy server, and the upstream or origin server which in most cases you may not have any control over. However, there are multiple potential causes of a 502 error and so solving it can be a time-consuming process. Referred to as an HTTP Status Code, this error indicates to web admins that something has been incorrectly configured on the server. Bad Gateway: The proxy server received an invalid response from an upstream server.502 Server Error: The server encountered a temporary error and could not complete your request.As a generic message, it can be displayed in many different ways and doesn’t actually tell you much more information to help troubleshoot.īelow are some common ways you might see it: A 502 Bad Gateway Error will often be seen when trying to access a specific webpage and generally an indicator that there’s something wrong with a website’s server communication.