"The requested URL cocould not be retrieved" appears when Squid proxy is used"

Problem:
When using a proxy to access a website, the following error occurs:
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The requested URL cocould not be retrieved

While trying to retrieve the URL: http://linkhelp.clients.google.com/tbproxy/lh/fixurl?

The following error was encountered:

Unable to determine IP address from host name for linkhelp.clients.google.com

The dnsserver returned:

Timeout

This means that:

The cache was not able to resolve the hostname presented in the URL.
Check if the address is correct.

Your cache administrator is root.
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Solution:
This is because the DNS configuration of the proxy server machine is incorrect. The proxy server machine cannot find the IP address of the specified URL. Check whether the/etc/resolv. conf file is correctly configured. If incorrect configuration information is added, for example:
Nameserver ###.###.###.###
Nameserver ###.###.###.###
You can configure multiple DNS servers.
Restart the squid service.