diff --git a/Dockerfile b/Dockerfile
index cf1c59f..a10430e 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -11,9 +11,7 @@ RUN docker-php-ext-install gettext && docker-php-ext-enable gettext
 RUN docker-php-ext-install intl && docker-php-ext-enable intl
 RUN docker-php-ext-install zip && docker-php-ext-enable zip
 RUN docker-php-ext-install ldap && docker-php-ext-enable ldap
-RUN wget -O wikindx.tar.bz2 https://phoenixnap.dl.sourceforge.net/project/wikindx/6.4.9/wikindx_6.4.9.tar.bz2
-RUN tar jxf wikindx.tar.bz2
-RUN cp wikindx/config.php.dist wikindx/config.php
+
 COPY create.sql .
 COPY docker-entrypoint-wikindx /usr/local/bin/
 RUN chown www-data.www-data wikindx -R
@@ -27,4 +25,9 @@ RUN echo "mysqli.default_socket = /var/run/mysqld/mysqld.sock" >> /usr/local/etc
 VOLUME ["/var/lib/mysql"]
 VOLUME ["/home/wikindx"]
 
+RUN mkdir /home/wikindx
+WORKDIR /var/www/html
+RUN wget -O wikindx.tar.bz2 https://phoenixnap.dl.sourceforge.net/project/wikindx/6.4.9/wikindx_6.4.9.tar.bz2
+RUN tar jxf wikindx.tar.bz2
+
 ENTRYPOINT ["docker-entrypoint-wikindx"]
diff --git a/docker-entrypoint-wikindx b/docker-entrypoint-wikindx
index f7389bd..1a98c48 100755
--- a/docker-entrypoint-wikindx
+++ b/docker-entrypoint-wikindx
@@ -7,8 +7,23 @@ if [ ! -d /var/lib/mysql/wikindx6 ] ; then
   mysql -u root < create.sql
 fi
 
-if [ ! -d /var/www/html/wikindx ]; then
-  mv /home/wikindx /var/www/html/
+# for updating from old docker container
+if [ -d /home/wikindx/core ]; then
+  mv /home/wikindx/config.php /tmp/
+  rm /home/wikindx/* -rf
+  mv /tmp/config.php /home/wikindx/config.php
+  chown -R www-data.www-data /home/wikindx
+fi
+
+# make sure a configuration file exists
+if [ ! -e /home/wikindx/config.php ]; then
+  cp /var/www/html/config.php.dist /home/wikindx/config.php
+  chown -R www-data.www-data /home/wikindx
+fi
+
+# make sure configuration file is linked to application directory
+if [ ! -e /var/www/html/config.php ]; then
+  ln -s /home/wikindx/config.php /var/www/html/config.php
   chown -R www-data.www-data /var/www/html/wikindx
 fi