I am using XAMPP as server in ubuntu 14.04 VPS of digitalocean. I tried to setup virtual hosts. But it is not working and I am getting 403 error of access denied.

I changed files too. My files with changes are

/opt/lampp/etc/httpd.conf

#
# This is the main Apache HTTP server configuration file.  It contains the
# configuration directives that give the server its instructions.
# See <URL:http://httpd.apache.org/docs/trunk/> for detailed information.
# In particular, see 
# <URL:http://httpd.apache.org/docs/trunk/mod/directives.html>
# for a discussion of each configuration directive.
#
# Do NOT simply read the instructions in here without understanding
# what they do.  They're here only as hints or reminders.  If you are unsure
# consult the online docs. You have been warned.  
#
# Configuration and logfile names: If the filenames you specify for many
# of the server's control files begin with "/" (or "drive:/" for Win32), the
# server will use that explicit path.  If the filenames do *not* begin
# with "/", the value of ServerRoot is prepended -- so 'log/access_log'
# with ServerRoot set to '/www' will be interpreted by the
# server as '/www/log/access_log', where as '/log/access_log' will be
# interpreted as '/log/access_log'.

#
# ServerRoot: The top of the directory tree under which the server's
# configuration, error, and log files are kept.
#
# Do not add a slash at the end of the directory path.  If you point
# ServerRoot at a non-local disk, be sure to specify a local disk on the
# Mutex directive, if file-based mutexes are used.  If you wish to share the
# same ServerRoot for multiple httpd daemons, you will need to change at
# least PidFile.
#
ServerRoot "/opt/lampp"

# 
# Mutex: Allows you to set the mutex mechanism and mutex file directory
# for individual mutexes, or change the global defaults
# 
# Uncomment and change the directory if mutexes are file-based and the default
# mutex file directory is not on a local disk or is not appropriate for some
# other reason.
#
# Mutex default:logs

#
# Listen: Allows you to bind Apache to specific IP addresses and/or
# ports, instead of the default. See also the <VirtualHost>
# directive.
#
# Change this to Listen on specific IP addresses as shown below to 
# prevent Apache from glomming onto all bound IP addresses.
#
#Listen 12.34.56.78:80
Listen 80

#
# Dynamic Shared Object (DSO) Support
#
# To be able to use the functionality of a module which was built as a DSO you
# have to place corresponding `LoadModule' lines at this location so the
# directives contained in it are actually available _before_ they are used.
# Statically compiled modules (those listed by `httpd -l') do not need
# to be loaded here.
#
# Example:
# LoadModule foo_module modules/mod_foo.so
#
LoadModule authn_file_module modules/mod_authn_file.so
LoadModule authn_dbm_module modules/mod_authn_dbm.so
LoadModule authn_anon_module modules/mod_authn_anon.so
LoadModule authn_dbd_module modules/mod_authn_dbd.so
LoadModule authn_socache_module modules/mod_authn_socache.so
LoadModule authn_core_module modules/mod_authn_core.so
LoadModule authz_host_module modules/mod_authz_host.so
LoadModule authz_groupfile_module modules/mod_authz_groupfile.so
LoadModule authz_user_module modules/mod_authz_user.so
LoadModule authz_dbm_module modules/mod_authz_dbm.so
LoadModule authz_owner_module modules/mod_authz_owner.so
LoadModule authz_dbd_module modules/mod_authz_dbd.so
LoadModule authz_core_module modules/mod_authz_core.so
LoadModule authnz_ldap_module modules/mod_authnz_ldap.so
LoadModule access_compat_module modules/mod_access_compat.so
LoadModule auth_basic_module modules/mod_auth_basic.so
LoadModule auth_form_module modules/mod_auth_form.so
LoadModule auth_digest_module modules/mod_auth_digest.so
LoadModule allowmethods_module modules/mod_allowmethods.so
LoadModule file_cache_module modules/mod_file_cache.so
LoadModule cache_module modules/mod_cache.so
LoadModule cache_disk_module modules/mod_cache_disk.so
LoadModule socache_shmcb_module modules/mod_socache_shmcb.so
LoadModule socache_dbm_module modules/mod_socache_dbm.so
LoadModule socache_memcache_module modules/mod_socache_memcache.so
LoadModule dbd_module modules/mod_dbd.so
LoadModule bucketeer_module modules/mod_bucketeer.so
LoadModule dumpio_module modules/mod_dumpio.so
LoadModule echo_module modules/mod_echo.so
LoadModule case_filter_module modules/mod_case_filter.so
LoadModule case_filter_in_module modules/mod_case_filter_in.so
LoadModule buffer_module modules/mod_buffer.so
LoadModule ratelimit_module modules/mod_ratelimit.so
LoadModule reqtimeout_module modules/mod_reqtimeout.so
LoadModule ext_filter_module modules/mod_ext_filter.so
LoadModule request_module modules/mod_request.so
LoadModule include_module modules/mod_include.so
LoadModule filter_module modules/mod_filter.so
LoadModule substitute_module modules/mod_substitute.so
LoadModule sed_module modules/mod_sed.so
LoadModule charset_lite_module modules/mod_charset_lite.so
LoadModule deflate_module modules/mod_deflate.so
LoadModule mime_module modules/mod_mime.so
LoadModule ldap_module modules/mod_ldap.so
LoadModule log_config_module modules/mod_log_config.so
LoadModule log_debug_module modules/mod_log_debug.so
LoadModule logio_module modules/mod_logio.so
LoadModule env_module modules/mod_env.so
LoadModule mime_magic_module modules/mod_mime_magic.so
LoadModule cern_meta_module modules/mod_cern_meta.so
LoadModule expires_module modules/mod_expires.so
LoadModule headers_module modules/mod_headers.so
LoadModule usertrack_module modules/mod_usertrack.so
LoadModule unique_id_module modules/mod_unique_id.so
LoadModule setenvif_module modules/mod_setenvif.so
LoadModule version_module modules/mod_version.so
LoadModule remoteip_module modules/mod_remoteip.so
LoadModule proxy_module modules/mod_proxy.so
LoadModule proxy_connect_module modules/mod_proxy_connect.so
LoadModule proxy_ftp_module modules/mod_proxy_ftp.so
LoadModule proxy_http_module modules/mod_proxy_http.so
LoadModule proxy_fcgi_module modules/mod_proxy_fcgi.so
LoadModule proxy_scgi_module modules/mod_proxy_scgi.so
LoadModule proxy_ajp_module modules/mod_proxy_ajp.so
LoadModule proxy_balancer_module modules/mod_proxy_balancer.so
LoadModule proxy_express_module modules/mod_proxy_express.so
LoadModule session_module modules/mod_session.so
LoadModule session_cookie_module modules/mod_session_cookie.so
LoadModule session_dbd_module modules/mod_session_dbd.so
LoadModule slotmem_shm_module modules/mod_slotmem_shm.so
LoadModule ssl_module modules/mod_ssl.so
LoadModule lbmethod_byrequests_module modules/mod_lbmethod_byrequests.so
LoadModule lbmethod_bytraffic_module modules/mod_lbmethod_bytraffic.so
LoadModule lbmethod_bybusyness_module modules/mod_lbmethod_bybusyness.so
LoadModule lbmethod_heartbeat_module modules/mod_lbmethod_heartbeat.so
LoadModule unixd_module modules/mod_unixd.so
LoadModule dav_module modules/mod_dav.so
LoadModule status_module modules/mod_status.so
LoadModule autoindex_module modules/mod_autoindex.so
LoadModule info_module modules/mod_info.so
LoadModule suexec_module modules/mod_suexec.so
LoadModule cgi_module modules/mod_cgi.so
LoadModule cgid_module modules/mod_cgid.so
LoadModule dav_fs_module modules/mod_dav_fs.so
LoadModule vhost_alias_module modules/mod_vhost_alias.so
LoadModule negotiation_module modules/mod_negotiation.so
LoadModule dir_module modules/mod_dir.so
LoadModule actions_module modules/mod_actions.so
LoadModule speling_module modules/mod_speling.so
LoadModule userdir_module modules/mod_userdir.so
LoadModule alias_module modules/mod_alias.so
LoadModule rewrite_module modules/mod_rewrite.so

<IfDefine JUSTTOMAKEAPXSHAPPY>
LoadModule php4_module        modules/libphp4.so
LoadModule php5_module        modules/libphp5.so
</IfDefine>

<IfModule unixd_module>
#
# If you wish httpd to run as a different user or group, you must run
# httpd as root initially and it will switch.  
#
# User/Group: The name (or #number) of the user/group to run httpd as.
# It is usually good practice to create a dedicated user and group for
# running httpd, as with most system services.
#
User root
Group www
</IfModule>

# 'Main' server configuration
#
# The directives in this section set up the values used by the 'main'
# server, which responds to any requests that aren't handled by a
# <VirtualHost> definition.  These values also provide defaults for
# any <VirtualHost> containers you may define later in the file.
#
# All of these directives may appear inside <VirtualHost> containers,
# in which case these default settings will be overridden for the
# virtual host being defined.
#

#
# ServerAdmin: Your address, where problems with the server should be
# e-mailed.  This address appears on some server-generated pages, such
# as error documents.  e.g. [email protected]
#
ServerAdmin [email protected]

#
# ServerName gives the name and port that the server uses to identify itself.
# This can often be determined automatically, but we recommend you specify
# it explicitly to prevent problems during startup.
#
# If your host doesn't have a registered DNS name, enter its IP address here.
#
#ServerName www.example.com:@@Port@@
# XAMPP
ServerName localhost

#
# Deny access to the entirety of your server's filesystem. You must
# explicitly permit access to web content directories in other
# <Directory> blocks below.
#
<Directory />
    AllowOverride none
    Require all denied
</Directory>

#
# Note that from this point forward you must specifically allow
# particular features to be enabled - so if something's not working as
# you might expect, make sure that you have specifically enabled it
# below.
#

# 
# DocumentRoot: The directory out of which you will serve your
# documents. By default, all requests are taken from this directory, but
# symbolic links and aliases may be used to point to other locations.
#
DocumentRoot "/opt/lampp/htdocs"
<Directory "/opt/lampp/htdocs">
    #
    # Possible values for the Options directive are "None", "All",
    # or any combination of:
    #   Indexes Includes FollowSymLinks SymLinksifOwnerMatch ExecCGI MultiViews
    #
    # Note that "MultiViews" must be named *explicitly* --- "Options All"
    # doesn't give it to you.
    #
    # The Options directive is both complicated and important.  Please see
    # http://httpd.apache.org/docs/trunk/mod/core.html#options
    # for more information.
    #
    #Options Indexes FollowSymLinks
    # XAMPP
    Options Indexes FollowSymLinks ExecCGI Includes

    #
    # AllowOverride controls what directives may be placed in .htaccess files.
    # It can be "All", "None", or any combination of the keywords:
    #   Options FileInfo AuthConfig Limit
    #
    #AllowOverride None
    # since XAMPP 1.4:
    AllowOverride All

    #
    # Controls who can get stuff from this server.
    #
    Require all granted
</Directory>

#
# DirectoryIndex: sets the file that Apache will serve if a directory
# is requested.
#
<IfModule dir_module>
    #DirectoryIndex index.html
    # XAMPP
    DirectoryIndex index.html index.html.var index.php index.php3 index.php4
</IfModule>

#
# The following lines prevent .htaccess and .htpasswd files from being 
# viewed by Web clients. 
#
<Files ".ht*">
    Require all denied
</Files>

#
# ErrorLog: The location of the error log file.
# If you do not specify an ErrorLog directive within a <VirtualHost>
# container, error messages relating to that virtual host will be
# logged here.  If you *do* define an error logfile for a <VirtualHost>
# container, that host's errors will be logged there and not here.
#
ErrorLog "logs/error_log"

#
# LogLevel: Control the number of messages logged to the error_log.
# Possible values include: debug, info, notice, warn, error, crit,
# alert, emerg.
#
LogLevel warn

<IfModule log_config_module>
    #
    # The following directives define some format nicknames for use with
    # a CustomLog directive (see below).
    #
    LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\"" combined
    LogFormat "%h %l %u %t \"%r\" %>s %b" common

    <IfModule logio_module>
      # You need to enable mod_logio.c to use %I and %O
      LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\" %I %O" combinedio
    </IfModule>

    #
    # The location and format of the access logfile (Common Logfile Format).
    # If you do not define any access logfiles within a <VirtualHost>
    # container, they will be logged here.  Contrariwise, if you *do*
    # define per-<VirtualHost> access logfiles, transactions will be
    # logged therein and *not* in this file.
    #
    CustomLog "logs/access_log" common

    #
    # If you prefer a logfile with access, agent, and referer information
    # (Combined Logfile Format) you can use the following directive.
    #
    #CustomLog "logs/access_log" combined
</IfModule>

<IfModule alias_module>
    #
    # Redirect: Allows you to tell clients about documents that used to 
    # exist in your server's namespace, but do not anymore. The client 
    # will make a new request for the document at its new location.
    # Example:
    # Redirect permanent /foo http://www.example.com/bar

    #
    # Alias: Maps web paths into filesystem paths and is used to
    # access content that does not live under the DocumentRoot.
    # Example:
    # Alias /webpath /full/filesystem/path
    #
    # If you include a trailing / on /webpath then the server will
    # require it to be present in the URL.  You will also likely
    # need to provide a <Directory> section to allow access to
    # the filesystem path.

    #
    # ScriptAlias: This controls which directories contain server scripts. 
    # ScriptAliases are essentially the same as Aliases, except that
    # documents in the target directory are treated as applications and
    # run by the server when requested rather than as documents sent to the
    # client.  The same rules about trailing "/" apply to ScriptAlias
    # directives as to Alias.
    #
    ScriptAlias /cgi-bin/ "/opt/lampp/cgi-bin/"

</IfModule>

<IfModule cgid_module>
    #
    # ScriptSock: On threaded servers, designate the path to the UNIX
    # socket used to communicate with the CGI daemon of mod_cgid.
    #
    #Scriptsock logs/cgisock
</IfModule>

#
# "/opt/lampp/cgi-bin" should be changed to whatever your ScriptAliased
# CGI directory exists, if you have that configured.
#
<Directory "/opt/lampp/cgi-bin">
    AllowOverride None
    Options None
    Require all granted
</Directory>

<IfModule mime_module>
    #
    # TypesConfig points to the file containing the list of mappings from
    # filename extension to MIME-type.
    #
    TypesConfig etc/mime.types

    #
    # AddType allows you to add to or override the MIME configuration
    # file specified in TypesConfig for specific file types.
    #
    #AddType application/x-gzip .tgz
    #
    # AddEncoding allows you to have certain browsers uncompress
    # information on the fly. Note: Not all browsers support this.
    #
    #AddEncoding x-compress .Z
    #AddEncoding x-gzip .gz .tgz
    #
    # If the AddEncoding directives above are commented-out, then you
    # probably should define those extensions to indicate media types:
    #
    AddType application/x-compress .Z
    AddType application/x-gzip .gz .tgz

    #
    # AddHandler allows you to map certain file extensions to "handlers":
    # actions unrelated to filetype. These can be either built into the server
    # or added with the Action directive (see below)
    #
    # To use CGI scripts outside of ScriptAliased directories:
    # (You will also need to add "ExecCGI" to the "Options" directive.)
    #
    #AddHandler cgi-script .cgi
    # XAMPP, since LAMPP 0.9.8:
    AddHandler cgi-script .cgi .pl

    # For type maps (negotiated resources):
    #AddHandler type-map var

    #
    # Filters allow you to process content before it is sent to the client.
    #
    # To parse .shtml files for server-side includes (SSI):
    # (You will also need to add "Includes" to the "Options" directive.)
    #
    # XAMPP
    AddType text/html .shtml
    AddOutputFilter INCLUDES .shtml
</IfModule>

#
# The mod_mime_magic module allows the server to use various hints from the
# contents of the file itself to determine its type.  The MIMEMagicFile
# directive tells the module where the hint definitions are located.
#
#MIMEMagicFile etc/magic

#
# Customizable error responses come in three flavors:
# 1) plain text 2) local redirects 3) external redirects
#
# Some examples:
#ErrorDocument 500 "The server made a boo boo."
#ErrorDocument 404 /missing.html
#ErrorDocument 404 "/cgi-bin/missing_handler.pl"
#ErrorDocument 402 http://www.example.com/subscription_info.html
#

#
# MaxRanges: Maximum number of Ranges in a request before
# returning the entire resource, or one of the special
# values 'default', 'none' or 'unlimited'.
# Default setting is to accept 200 Ranges.
#MaxRanges unlimited

#
# EnableMMAP and EnableSendfile: On systems that support it, 
# memory-mapping or the sendfile syscall may be used to deliver
# files.  This usually improves server performance, but must
# be turned off when serving from networked-mounted 
# filesystems or if support for these functions is otherwise
# broken on your system.
# Defaults: EnableMMAP On, EnableSendfile Off
#
EnableMMAP off
EnableSendfile off

# Supplemental configuration
#
# The configuration files in the etc/extra/ directory can be 
# included to add extra features or to modify the default configuration of 
# the server, or you may simply copy their contents here and change as 
# necessary.

# Server-pool management (MPM specific)
#Include etc/extra/httpd-mpm.conf

# Multi-language error messages
Include etc/extra/httpd-multilang-errordoc.conf

# Fancy directory listings
Include etc/extra/httpd-autoindex.conf

# Language settings
#Include etc/extra/httpd-languages.conf

# User home directories
#Include etc/extra/httpd-userdir.conf

# Real-time info on requests and configuration
#Include etc/extra/httpd-info.conf

# Virtual hosts
Include etc/extra/httpd-vhosts.conf

# Local access to the Apache HTTP Server Manual
#Include etc/extra/httpd-manual.conf

# Distributed authoring and versioning (WebDAV)
#Include etc/extra/httpd-dav.conf

# Various default settings
Include etc/extra/httpd-default.conf

# Configure mod_proxy_html to understand HTML4/XHTML1
<IfModule proxy_html_module>
Include etc/extra/proxy-html.conf
</IfModule>

# Secure (SSL/TLS) connections
<IfModule ssl_module>
# XAMPP
<IfDefine SSL>
Include etc/extra/httpd-ssl.conf
</IfDefine>
</IfModule>
#
# Note: The following must must be present to support
#       starting without SSL on platforms with no /dev/random equivalent
#       but a statically compiled-in mod_ssl.
#
<IfModule ssl_module>
SSLRandomSeed startup builtin
SSLRandomSeed connect builtin
</IfModule>

# XAMPP
Include etc/extra/httpd-xampp.conf
Include "/opt/lampp/apache2/conf/httpd.conf"

I used command shown in this example. I used below lines to change and add group

Add group "groupadd www"
Add user to group "usermod -aG www root"
Change htdocs group "chgrp -R www /opt/lampp/htdocs"
Change sitedir group "chgrp -R www /opt/lampp/htdocs/mysite"
Change htdocs chmod "chmod 2775 /opt/lampp/htdocs"
Change sitedir chmod "chmod 2775 /opt/lampp/htdocs/mysite"

And then I changed my vhosts.conf file

# Virtual Hosts
#
# Required modules: mod_log_config

# If you want to maintain multiple domains/hostnames on your
# machine you can setup VirtualHost containers for them. Most configurations
# use only name-based virtual hosts so the server doesn't need to worry about
# IP addresses. This is indicated by the asterisks in the directives below.
#
# Please see the documentation at 
# <URL:http://httpd.apache.org/docs/2.4/vhosts/>
# for further details before you try to setup virtual hosts.
#
# You may use the command line option '-S' to verify your virtual host
# configuration.

#
# VirtualHost example:
# Almost any Apache directive may go into a VirtualHost container.
# The first VirtualHost section is used for all requests that do not
# match a ServerName or ServerAlias in any <VirtualHost> block.
#
<VirtualHost *:80>
    ServerAdmin [email protected]
    DocumentRoot "/opt/lampp/docs/dummy-host.example.com"
    ServerName dummy-host.example.com
    ServerAlias www.dummy-host.example.com
    ErrorLog "logs/dummy-host.example.com-error_log"
    CustomLog "logs/dummy-host.example.com-access_log" common
</VirtualHost>

<VirtualHost *:80>
    ServerAdmin [email protected]
    DocumentRoot "/opt/lampp/docs/dummy-host2.example.com"
    ServerName dummy-host2.example.com
    ErrorLog "logs/dummy-host2.example.com-error_log"
    CustomLog "logs/dummy-host2.example.com-access_log" common
</VirtualHost>

NameVirtualHost *
<VirtualHost *>
    ServerAdmin [email protected]
    DocumentRoot "/opt/lampp/htdocs/mysite"
    ServerName mysite.com
    ServerAlias mysite.com
    ErrorLog "/opt/lampp/htdocs/mysite/errorlogs"
    CustomLog "/opt/lampp/htdocs/mysite/customlog" common
    <Directory "/opt/lampp/htdocs/mysite">
        Options Indexes FollowSymLinks Includes ExecCGI
        AllowOverride All
        Order Allow,Deny
        Allow from all
        Require all granted
    </Directory>
</VirtualHost>

but still its not working and I am getting 403 error on my ip and domain however I can access phpmyadmin. If anyone can help me, please help me.