Error when I click play/download

I get an error message when I click play/download on minecraft PC. Unable to save download. fa_ir.lang
Name: fa_ir.lang
URL: http://resources.download.minecraft.net/7e/7e9b6d4ef58362b090b2c1dd3f2f403c4b187a3e
Error details: Attempting to move successful download to C:/Users\thega\AppData\Roaming\.minecraft\assets\objects\7e/7e9b6d4ef58362b090b2c1dd3f2f403c4b187a3e
The process cannot access the file because it is being used by another process
Filename on disk: 7c2d-09b3-d74d-d90d
Path: C:\Users\thega\AppData\Local\Temp\7c2d-09b3-d74d-d90d
Exists: file