During the Vivado 2014.1 install process, once I've selected my desired options, the download fails immediately.
An error message similar to the following appears.
Error Downloading Files There was an unexpected error creating C:\Users\my_user_name\AppData\Local\Temp\xinstall\bin\..., system error message was NA.
This issue will occur for users that do the following:
The work around is to cancel and close the installation, then restart it.
Select the Download and Install option, provide a user ID and password and complete the installation process as normal.