Error "Proxy does not allow connections" during Web Connections

Symptoms

Browser displays "proxy does not allow connections" or similar error message when connecting to web targets.

Solution

Squid service is not running on web proxy machine. Verify and restart Squid if necessary:

# systemctl status squid
# systemctl restart squid

You may also check Squid logs under /var/log/squid/ for additional information about the issue.