Windows 8.1 update 1 KB2919355 direct download
http://www.microsoft.com/en-us/download ... x?id=42335
if errors you may want to read this, generally its the same issue as 8 to 8.1 when you have moved your users to another disk
Installation Failure: Windows failed to install the following update with error 0x80070005: Update for Windows (KB2919355).
had to copy c:\users\Default to d:\user\Default and reboot
http://chentiangemalc.wordpress.com/201 ... -update-1/