diff --git a/start.sh b/start.sh
index f38a861..735cde5 100755
--- a/start.sh
+++ b/start.sh
@@ -1,7 +1,7 @@
 #!/bin/sh
 
 USER_NAME=${USER_NAME:-nextcloudclient}
-USER_GRP=${USER_NAME}
+USER_GROUP=${USER_GROUP:-nextcloudgroup}
 USER_UID=${USER_UID:-1000}
 USER_GID=${USER_GID:-1000}
 NEXTCLOUD_USERNAME=${NEXTCLOUD_USERNAME:-username}
@@ -10,9 +10,23 @@ NEXTCLOUD_URL=${NEXTCLOUD_URL:-https://nextcloud.example.com}
 NEXTCLOUD_DIR=${NEXTCLOUD_DIR:-/data}
 NEXTCLOUD_DIR_CHOWN=${NEXTCLOUD_DIR_CHOWN:-1}
 
-# create the user/group
-addgroup -g ${USER_GID} ${USER_GRP}
-adduser -s /bin/false -D -H -G ${USER_GRP} -u ${USER_UID} ${USER_NAME}
+# check if group already exists
+GRP_NAME=$(getent group ${USER_GID} )
+if [ "${GRP_NAME}" ] ; then
+	USER_GROUP=$( echo ${GRP_NAME} | sed 's/\:.*//' )
+else
+	# if not, we create the group
+	addgroup -g ${USER_GID} ${USER_GROUP}
+fi
+
+# check if user already exists
+USR_NAME=$(getent passwd ${USER_UID} )
+if [ "${USR_NAME}" ] ; then
+	USER_NAME=$( echo ${USR_NAME} | sed 's/\:.*//' )
+else
+	# if not, we create the user
+	adduser -s /bin/false -D -H -G ${USER_GROUP} -u ${USER_UID} ${USER_NAME}
+fi
 
 # create dir if not exists (it should exist if you mapped it outside the container)
 if [ ! -d "${NEXTCLOUD_DIR}" ] ; then