Answers.Body: <p>I finally succeeded to find the solution!</p>
  
  <p>It was the VirtualHost's <strong>include_path</strong> the problem! In fact it seems that CiviCRM's install script needs to add paths in it, and if it is already set, it cannot be modified with the PHP's native function <code>set_include_path(void)</code>.</p>
  
  <p>So, I only had to <strong>comment the VirtualHost's include_path</strong>, and it worked!</p>
  
  <p>My VirtualHost looks like that now:</p>
  
  <blockquote>
  <pre><code> &lt;VirtualHost 192.168.1.203:80&gt;
       ServerName xxxx
       SetEnv CODE_SITE xxxx
       DocumentRoot /var/www/xxxx  
       php_admin_flag  engine on
       #php_admin_value include_path "/var/www/xxxx/" =&gt; this line must be deleted
  &lt;/VirtualHost&gt;
  </code></pre>
  </blockquote>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2015-09-01T11:42:28.523Z
Answers.LastActivityDate: 2015-09-01T11:42:28.523Z
Answers.UserDisplayName: Kesako Gozaimasu
Body: <p>I tried all the day to install version <strong>4.6.x of CiviCRM</strong> on a brand new installation of <strong>Drupal 7.39</strong>, but each time I execute the installation here:</p>
  
  <pre><code>http://&lt;your_drupal_home&gt;/sites/all/modules/civicrm/install/index.php
  </code></pre>
  
  <p>I get a blank page and the following error in my logs :</p>
  
  <pre><code>PHP Fatal error: Class 'CRM_Core_Config' not found in /var/www/xxxx/sites/all/modules/civicrm/install/index.php on line 142
  </code></pre>
  
  <p>The method I used to install is simply downloading the compressed tarball and untaring it in the folder <strong>/var/www/xxxx/sites/all/modules/</strong>, and this after just having completed the installation of Drupal.</p>
  
  <p>My confiuration is :</p>
  
  <ul>
  <li><p>Debian GNU/Linux 8 (jessie) server <strong>with a private IP</strong></p></li>
  <li><p>Apache/2.4.10 (Debian)</p></li>
  <li><p>PHP Version 5.6.7-1 (with all prerequisites except using the PHP's bundled version of PCRE for which I cannot guarantee it has the <strong>unicode properties support</strong>)</p></li>
  <li><p>Content of the VirtualHost :</p></li>
  </ul>
  
  <blockquote>
  <pre><code> &lt;VirtualHost 192.168.1.203:80&gt;
       ServerName xxxx
       SetEnv CODE_SITE xxxx
       DocumentRoot /var/www/xxxx  
       php_admin_flag  engine on
       php_admin_value include_path "/var/www/xxxx/"
  &lt;/VirtualHost&gt;
  </code></pre>
  </blockquote>
  
  <p><strong>EDIT 1</strong></p>
  
  <blockquote>
    <p>Nom I am sure that the PCRE version bundled in my PHP instance has the <strong>unicode properties support</strong> option enabled, since I could sucessfully execute (with no warnings) : <code>if(preg_match('/^\p{Arabic}+$/u', 'ﻎﺤﺤﺤﺤﺤﺣ')) echo 'OK'; else echo 'KOOOOOO'</code> and it displayed <strong>OK</strong></p>
  </blockquote>
  
  <p>Does anyone have any idea ?</p>
  
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2015-08-26T14:50:26.157Z
Comments.Text: Just checking, but are you certain you downloaded the correct version of CiviCRM (for Drupal 7, not Drupal 6 or another CMS)?
Comments.UserDisplayName: Laryn
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2015-08-26T14:58:46.187Z
Comments.Text: also check file permissions are correct before beginning installation process...
Comments.UserDisplayName: Tapash
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2015-08-26T15:20:14.120Z
Comments.Text: @Laryn Yes, I installed the right version, I even installed and uninstalled it a lot of times (from https://download.civicrm.org/civicrm-4.6.8-drupal.tar.gz)
Comments.UserDisplayName: Kesako Gozaimasu
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2015-08-26T15:21:19.360Z
Comments.Text: @KesakoGozaimasu Do you get the installation screen, or the error screen immediately?
Comments.UserDisplayName: Laryn
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2015-08-26T15:23:48.013Z
Comments.Text: @Tapash yes, I put all the permissions "rwx" for "www-data" user and group
Comments.UserDisplayName: Kesako Gozaimasu
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2015-08-26T15:24:47.900Z
Comments.Text: @Laryn I get a blank page, but when I check in my logs i get the error i mentionned
Comments.UserDisplayName: Kesako Gozaimasu
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2015-08-26T15:49:49.897Z
Comments.Text: @KesakoGozaimasu Any other modules installed on Drupal, or is it a blank Drupal installation?
Comments.UserDisplayName: Laryn
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2015-08-26T16:17:29.833Z
Comments.Text: @Laryn it's a blank Drupal installation and I have a virtualhost that is really minimalist (see the question post I just added the content of my virtualhost file)
Comments.UserDisplayName: Kesako Gozaimasu
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2015-08-26T16:18:33.363Z
Comments.Text: All other notes on here are okay on your setup? http://wiki.civicrm.org/confluence/display/CRMDOC/CiviCRM+PHP+Requirements
Comments.UserDisplayName: Laryn
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2015-08-26T16:42:21.447Z
Comments.Text: You mention trying the install multiple times.  Are you sure a previous attempt didn't do a partial install and quit (for a different reason).  It sounds like it is partially installed.
Comments.UserDisplayName: DaveD
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2015-08-27T06:48:35.380Z
Comments.Text: @DaveD when I said "install", I simply mean I untared and decompressed the tarball of the module in /var/www/xxxx/sites/all/modules/, but the following step to complete the installation is to execute the http://<your_drupal_home>/sites/all/modules/civicrm/install/index.php link and it is at that point that I get a blank page.
Comments.UserDisplayName: Kesako Gozaimasu
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2015-08-27T06:52:07.027Z
Comments.Text: @Laryn yes, I already checked, and everything is conform on my server according to the link you gave.
Comments.UserDisplayName: Kesako Gozaimasu
Tags: <drupal><logs><installation><links>
Title: Unable to install v.4.6.x - Drupal7
ThreadText: # Unable to install v.4.6.x - Drupal7
  
  (Asked by: username_0 on 2015-08-26)
  
  I tried all the day to install version 4.6.x of CiviCRM on a brand new installation of Drupal 7.39, but each time I execute the installation here:
  http:///sites/all/modules/civicrm/install/index.php
  
  I get a blank page and the following error in my logs :
  PHP Fatal error: Class 'CRM_Core_Config' not found in /var/www/xxxx/sites/all/modules/civicrm/install/index.php on line 142
  
  The method I used to install is simply downloading the compressed tarball and untaring it in the folder /var/www/xxxx/sites/all/modules/, and this after just having completed the installation of Drupal.
  My confiuration is :
  
  Debian GNU/Linux 8 (jessie) server with a private IP
  Apache/2.4.10 (Debian)
  PHP Version 5.6.7-1 (with all prerequisites except using the PHP's bundled version of PCRE for which I cannot guarantee it has the unicode properties support)
  Content of the VirtualHost :
  
  
   
       ServerName xxxx
       SetEnv CODE_SITE xxxx
       DocumentRoot /var/www/xxxx  
       php_admin_flag  engine on
       php_admin_value include_path "/var/www/xxxx/"
  
  
  
  EDIT 1
  
  Nom I am sure that the PCRE version bundled in my PHP instance has the unicode properties support option enabled, since I could sucessfully execute (with no warnings) : if(preg_match('/^\p{Arabic}+$/u', 'ﻎﺤﺤﺤﺤﺤﺣ')) echo 'OK'; else echo 'KOOOOOO' and it displayed OK
  
  Does anyone have any idea ?
  
  **Tags:** drupal, logs, installation, links
  
  > **Comments:**
  > **username_1**: Just checking, but are you certain you downloaded the correct version of CiviCRM (for Drupal 7, not Drupal 6 or another CMS)?  
  > **username_2**: also check file permissions are correct before beginning installation process...  
  > **username_0**: @username_1 Yes, I installed the right version, I even installed and uninstalled it a lot of times (from https://download.civicrm.org/civicrm-4.6.8-drupal.tar.gz)  
  > **username_1**: @KesakoGozaimasu Do you get the installation screen, or the error screen immediately?  
  > **username_0**: @username_2 yes, I put all the permissions "rwx" for "www-data" user and group  
  > **username_0**: @username_1 I get a blank page, but when I check in my logs i get the error i mentionned  
  > **username_1**: @KesakoGozaimasu Any other modules installed on Drupal, or is it a blank Drupal installation?  
  > **username_0**: @username_1 it's a blank Drupal installation and I have a virtualhost that is really minimalist (see the question post I just added the content of my virtualhost file)  
  > **username_1**: All other notes on here are okay on your setup? http://wiki.civicrm.org/confluence/display/CRMDOC/CiviCRM+PHP+Requirements  
  > **username_3**: You mention trying the install multiple times.  Are you sure a previous attempt didn't do a partial install and quit (for a different reason).  It sounds like it is partially installed.  
  > **username_0**: @username_3 when I said "install", I simply mean I untared and decompressed the tarball of the module in /var/www/xxxx/sites/all/modules/, but the following step to complete the installation is to execute the http://<your_drupal_home>/sites/all/modules/civicrm/install/index.php link and it is at that point that I get a blank page.  
  > **username_0**: @username_1 yes, I already checked, and everything is conform on my server according to the link you gave.  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_0 on 2015-09-01. Score: 3 | Accepted answer
  
  I finally succeeded to find the solution!
  It was the VirtualHost's include_path the problem! In fact it seems that CiviCRM's install script needs to add paths in it, and if it is already set, it cannot be modified with the PHP's native function set_include_path(void).
  So, I only had to comment the VirtualHost's include_path, and it worked!
  My VirtualHost looks like that now:
  
   
       ServerName xxxx
       SetEnv CODE_SITE xxxx
       DocumentRoot /var/www/xxxx  
       php_admin_flag  engine on
       #php_admin_value include_path "/var/www/xxxx/" => this line must be deleted
  
  
  ---
  
  