LoL uninstalls itself while playing

It just happened to me for the second time in the last 2 weeks. Every time when I was in game I lost connection and couldn't reconnect any more. When I wanted to re-open the game I got the message that the game was no longer installed on my pc. Did anyone else had this issue? What can I do to prevent it from happening next time?
Report as:
Offensive Spam Harassment Incorrect Board