Problème d'installation de Elgg

Bonjour,
Je rencontre un problème à l'installation de "Elgg.", au niveau de "Requirements check", j'ai ça :

Requirements check 

Your server failed the requirements check. After you have fixed the below issues, refresh this page. Check the troubleshooting links at the bottom of this page if you need further assistance. 

PHP 
Your server's PHP satisfies all of Elgg's requirements. 

Web server 
We think your server is running the Apache web server. 

The rewrite test failed and the most likely cause is that AllowOverride is not set to All for Elgg's directory. This prevents Apache from processing the .htaccess file which contains the rewrite rules. 

A less likely cause is Apache is configured with an alias for your Elgg directory and you need to set the RewriteBase in your .htaccess. There are further instructions in the .htaccess file in your Elgg directory.

Database 
The database requirements are checked when Elgg loads its database.

Mais le problème, c'est que le texte souligné est en faite en rouge, pourtant, je suis hébergé chez 1&1 sans problème ... Une idée ?

Merci beaucoup !


Mr. THZ
Think different with Mr. THZ