Internal Server Error After Zend Server Installation



After Zend Server successful installation, accessing the user application or website results in "Internal Server Error" browser page.

This article will cover common scenarios which can lead to this problem, and their practical solutions.

Scenario: System "PATH" contains Illegal XML characters

Applies To: Windows OS, Zend Server with Apache (Zend Enabler FastCGI Wrapper)

When Zend Server is installed, Zend Enabler is taking the system Environment Variable %PATH% and embeds it in a configuration file called "ZendEnablerConf.xml".

If the PATH contains characters which are invalid for XML, Zend Enabler will not be able to load the configuration file, and Apache will not be able to process PHP scripts through the PHP-CGI process pool which Zend Enabler should raise.

Check and Fix:

1. Backup, then edit with a simple text editor, the following configuration file:

C:\Program Files (x86)\Zend\ZendServer\etc\ZendEnablerConf.xml

2. Locate the line with <Variable name="PATH"

3. In the value="<PATH>" part, locate any illegal characters (such as "&") which the <PATH> text contains, then replace invalid characters with their XML valid entities - see Escaping reference. A common example is With "&" character - you need to replace it with "&amp;".


<Variable name="PATH" value="c:\m&m;C:\Windows;C:\Windows\system32" />


<Variable name="PATH" value="c:\m&amp;m;C:\Windows;C:\Windows\system32" />

4. After you escape all the invalid XML characters, save ZendEnablerConf.xml, and restart Apache. You can restart Apache using the Apache Monitor application, which usually resides in the system tray, or open a CMD console window, and type:

> net stop Apache2.2-Zend

> net start Apache2.2-Zend

Or, you can open services.msc (Services under Control Panel), locate ApacheX.Y-Zend, right click and on the context menu click on "Restart".


In case the above information is not helpful in solving your "Internal Server Error" problem, please open a support ticket and refer to this KB article, so we can enhance it with relevant information from your report.


  • Avatar
    Pedro Fidelis

    You saved my life! just because of a "&" character on my user account... THANK YOU VERY MUCH!