If you receive an error message with numbers end with (-4), the computer fails to install "Microsoft Visual C++ 2008 redistributable package" included in VOCALOID3 product installer program.

Please download and install "vcredist_x86.exe" manually from the link below, and then try installing VOCALOID3 products.

http://www.microsoft.com/en-us/download/details.aspx?id=26368

And if you fail to install "vcredist_x86.exe" downloaded from the link above, try "System Update Tool" from the link below, and then try following above steps.

http://windows.microsoft.com/en-us/windows7/What-is-the-System-Update-Readiness-Tool