Invalid command VirtualDocumentRoot perhaps misspelled apache failur error

So you got the above error ha? I have been dealing with that as well. Here is the solution.
The root of the problem is mod_vhost_alias.so file.
This file would be used to enable the the mod_vhost_alias. Once this is enabled you are done.

Step 1.
go to

/usr/lib/apache2/modules

and verify the file mod_vhost_alias.so exists. If not, google that file and put it there

Step 2.
go to

/etc/apache2/mods-enabled 

and create a file named vhost_alias.load

vi vhost_alias.load

and put the following inside it

LoadModule vhost_alias_module /usr/lib/apache2/modules/mod_vhost_alias.so

Step 3.
Do step 2 inside mods-available
Step 4.
restart apache

sudo /etc/init.d/apache2 restart

Step 5
Show face!!
This analogy can be used for errors like

Invalid Command ‘SSLEngine’, perhaps misspelled or defined by a module not included in the server configuration. Action ‘configtest’ failed’
and for
Invalid Command ‘rewriteengine’, perhaps misspelled or defined by a module not included in the server configuration. Action ‘configtest’ failed’

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