I was trying to install LOL. I got to the screen that allows you to log in, the thing is, the percentage bar goes back to 0%. Many people say that it goes down but keeps downloading whats missing. But it doesn't, it goes all the way down to 13GB when it left at 5GB , I have been trying to download this for three days now and it keeps going on, I do not have any idea how to fix it.
League-of-legends – Why is the LOL client resetting the download
league-of-legendstechnical-issues
Related Solutions
This picture that I just saw on League of Legends Reddit has a good way of explaining why and when it resets.
When someone attacks (leashes) blue buff, it will attempt to move towards that player to attack. However, blue buff can not move outside of its indicated aggro range. If the player that attacked blue first is still within its aggro range, it will continue to try and reach that player. When it can not, and it reaches its aggro range border, it will soft reset up to a maximum of 2 times. If the player that attacked it first leaves aggro range, it will continue to try, and move towards that player until it reaches its aggro range again. When it does, it will attempt to attack a player that is within the aggro range (and has attacked blue). Hard resets happen when it soft resets 2 times, then resets again. It will return to its original spawning location, ignoring all actions made by players.
You should put those settings in the designed steam option for the game.
Right click on CS:GO -> properties. Select set launch options... and type your settings
Example: 
This will save your settings.
Best Answer
Restart of update download may occur when is error thrown while downloading updates.
Next reason shlould be: