I have a new laptop and so far have been able to play minecraft with out problems. However recently when the launcher changed I get an error when I try to open the game.

it starts 'downloading' and then I get this error..
Unable to save download. mn_mn.lang
when I look for more information this is what I see...

ERROR

Unable to save download. ms_my.lang
Name: ms_my.lang
URL: http://resources.download.minecraft.net/13/137cc3930a6f600c045ed5ec40bba3e628cc1d64
Error details: Attempting to move successful download to C:/Users\User\AppData\Roaming\.minecraft\assets\objects\13/137cc3930a6f600c045ed5ec40bba3e628cc1d64 The process cannot access the file because it is being used by another process
Filename on disk: 0573-bc9c-721f-eacd
Path: C:\Users\User\AppData\Local\Temp\0573-bc9c-721f-eacd
Exists: file

I'm sorry If this issue has been resolved elsewhere and I'm just being dense, just not sure what to do. My old PC is playing the game fine but I cant get it to work here
thanks in advance