When opeing monecraft a message of "Unable to save download" pops up

Name: da_dk.lang
URL: http://resources.download.minecraft.net/3d/3d75feab34656d04562405b972ac06d2b2405deb
Error details: Attempting to move successful download to C:/Users\marci\AppData\Roaming\.minecraft\assets\objects\3d/3d75feab34656d04562405b972ac06d2b2405deb The process cannot access the file because it is being used by another process
Filename on disk: c986-c7cc-bdd3-376e
Path: C:\Users\marci\AppData\Local\Temp\c986-c7cc-bdd3-376e
Exists: file