Problem: Unable to rename file/folder. Mobile app hangs and browser GUI gives "Could not rename file/folder" error. Log shows locked file error.

Solution:
1. Install redis-server and php-redis if not already installed
2. Add to your OwnCloud config file (/var/www/owncloud/config/config.php or similar):
'memcache.local' => '\OC\Memcache\Redis',
'memcache.locking' => '\OC\Memcache\Redis',
3. Edit or add to the Redis config file (/etc/redis/redis.conf):
bind localhost [eth1 IP address]
4. Restart apache and redis-server