Unable to save download.

Whenever I try to start up Minecraft with the new launcher, it says "Unable to save download."

REPORT:

Unable to save download. client-1.7.xml
Name: client-1.7.xml
URL: https://launchermeta.mojang.com/mc/log_configs/client-1.7.xml/6605d632a2399010c0085d3e4da58974d62ccdfe/client-1.7.xml
Error details: Attempting to move successful download to C:/Users****\AppData\Roaming\.minecraft\assets\log_configs\client-1.7.xml
The process cannot access the file because it is being used by another process
Filename on disk: 550c-8914-b95e-6f35
Path: C:\Users****\AppData\Local\Temp\550c-8914-b95e-6f35
Exists: file