Apache Invalid command 'ProxyPass'?

Invalid command 'ProxyPass', perhaps misspelled or defined by a module not included in the server configuration
Action 'configtest' failed.

If you are using Linux Ubuntu operating system and have setup apache web server. In some case if you get the error mentioned in question description and want to solve it, for that you just need to install proxy module and restart apache and it will solve your problem. Below are the steps to solve this issue:

sudo a2enmod proxy

sudo a2enmod proxy_http

sudo systemctl restart apache2

Hope you solved your problem with thses steps.