I will press play and it will say preparing and then show a error

Ok so i will start my minecraft and press play and i will get a bar at the bottom that says preparing and will get about half way throught loading and then i will get a this error Name: eu_es.lang
URL: http://resources.download.minecraft.net/76/76ebb3988b7c1cdf9f5d22e96307716aebb32f9e
Error details: Attempting to move successful download to C:/Users\BeatB\AppData\Roaming\.minecraft\assets\objects\76/76ebb3988b7c1cdf9f5d22e96307716aebb32f9e The process cannot access the file because it is being used by another process
Filename on disk: e11a-f5fe-1ea9-464c
Path: C:\Users\BeatB\AppData\Local\Temp\e11a-f5fe-1ea9-464c
Exists: file