WAMP Server Your Projects urls are invalid & do n't work - windows-7

Question

I installed latest x64 wamp server : wampserver3.1.0_x64.exe On Windows 7.
I changed it's default 80 port to 8080, because of IIS & now every thing is ok.
I added a simple project to this path : C:\wamp64\www like below :
C:\wamp64\www\php_test\index.php
<?php
// Show all information, defaults to INFO_ALL
phpinfo();
?>
Now when i go to this path http://localhost:8080/ > Your Projects Area >
php_test > It's link is like this > http://php_test:8080/ > That does not work & is invalid.
The true link is : http://localhost:8080/php_test
How can i fix this problem?
I found the link below for that :
Project Links do not work on Wamp Server
I followed the answer.
Now the new problem is after adding virtual hosts, phptest does not work again.
Here is httpd-vhosts.conf file :
# Virtual Hosts
#
<VirtualHost *:8080>
ServerName localhost
ServerAlias localhost
DocumentRoot "${INSTALL_DIR}/www"
<Directory "${INSTALL_DIR}/www/">
Options +Indexes +Includes +FollowSymLinks +MultiViews
AllowOverride All
Require local
</Directory>
</VirtualHost>
<VirtualHost *:8080>
ServerName phptest
DocumentRoot "${INSTALL_DIR}/www/php_test"
<Directory "${INSTALL_DIR}/www/php_test/">
Options +Indexes +Includes +FollowSymLinks +MultiViews
AllowOverride All
Require local
</Directory>
</VirtualHost>
I did restart all services after adding phptest to virtual hosts.
My questions :
1. How can i fix that invalid link?
2. How make virtual hosts workable?
EDIT After Comments > Here is my HOSTS file content :
# Copyright (c) 1993-2009 Microsoft Corp.
#
# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.
#
# This file contains the mappings of IP addresses to host names. Each
# entry should be kept on an individual line. The IP address should
# be placed in the first column followed by the corresponding host name.
# The IP address and the host name should be separated by at least one
# space.
#
# Additionally, comments (such as these) may be inserted on individual
# lines or following the machine name denoted by a '#' symbol.
#
# For example:
#
# 102.54.94.97 rhino.acme.com # source server
# 38.25.63.10 x.acme.com # x client host
# localhost name resolution is handled within DNS itself.
# 127.0.0.1 localhost
# ::1 localhost
#
#

Answer 1

Your HOSTS file is basically empty as a # is a comment.
You have to add a reference to each VHOST into your HOSTS file like this so that the browser can find your development domains
Hosts file
127.0.0.1 localhost
::1 localhost
127.0.0.1 phptest
::1 phptest
Now you must restart the DNS Cache like this, from a command prompt that you have started "As an Administrator" or just reboot the PC
>net stop dnscache
When that has completed do
>net start dnscache
Or there is a menu item on WAMPServers menus
[Right Click] wampmanager-> Tools -> Restart DNS