virtualbox.org

Cannot install Windows 8.1 in VB. The installation process halts with an error code 0x000000C4
Please help.

Guest machine configuration:
Ram:2Gb
HDD: 25GB

Host OS: Ubuntu 14.04

That usually pops up if the vm is not configured correctly. Make sure that it is set to Windows 8.1 (64bit). Windows 8 config will not work for 8.1 .