diff --git a/2.-Installation-guide.md b/2.-Installation-guide.md
index ec8d129..c93ef0c 100644
--- a/2.-Installation-guide.md
+++ b/2.-Installation-guide.md
@@ -29,6 +29,7 @@ libauthen-pam-perl
 libnet-smtps-perl 
 libconfig-general-perl 
 libdigest-sha-perl
+wkhtmltopdf
 ```
 
 Webserver apache2 needs some modules loaded
@@ -73,7 +74,12 @@ cd /var/www/copri4/main
 ln -s /var/www/copri4external external
 chgrp -R www-data external/*
 ```
-
+For the creation of PDF files we use the program "wkhtmltopdf".
+```
+cd /var/www/copri4/main/src
+ln -s /usr/bin/wkhtmltopdf wkhtmltopdf-amd64
+```
+ 
 Setup the base copri database. You have to configure postgres to get just access by localhost. Set your postgres access rights.
 
 ```