Crash

Unable to save download. nn_no.lang
Name: nn_no.lang
URL: http://resources.download.minecraft.net/1c/1ce2fb3b05e30898ccd23e1c1257640c7e2b7658
Error details: Attempting to move successful download to C:/Users\David\AppData\Roaming\.minecraft\assets\objects\1c/1ce2fb3b05e30898ccd23e1c1257640c7e2b7658 The process cannot access the file because it is being used by another process
Filename on disk: 5312-525b-2e44-4d85
Path: C:\Users\David\AppData\Local\Temp\5312-525b-2e44-4d85
Exists: false

please help me quick