diff --git a/nextcloud/rootfs/etc/cont-init.d/01-folders.sh b/nextcloud/rootfs/etc/cont-init.d/01-folders.sh
index 434ffcaf7..024922c2d 100755
--- a/nextcloud/rootfs/etc/cont-init.d/01-folders.sh
+++ b/nextcloud/rootfs/etc/cont-init.d/01-folders.sh
@@ -13,13 +13,16 @@ chown -R "$PUID:$PGID" "/data/config"
 # Check current version
 if [ -f /data/config/www/nextcloud/config/config.php ]; then
     datadirectory="$(sed -n "s|.*datadirectory' => '*\(.*[^ ]\) *',.*|\1|p" /data/config/www/nextcloud/config/config.php)"
-echo "... Data directory detected : $datadirectory"
-
+    echo "... Data directory detected : $datadirectory"
 else
     datadirectory=/share/nextcloud
 fi
 
-
+# Is the directory valid
+if [[ "$datadirectory" == *"/mnt/"* ]] && [ ! -f "$datadirectory"/index.html ]; then
+    bashio::log.fatal "Data directory does not seem to be valid. Is your drive connected? Stopping to avoid corrupting the data directory."
+    bashio::addon.stop
+fi
 
 mkdir -p "$datadirectory"
 chmod 755 -R "$datadirectory"