Thanks but I find the solution, just delete files from the old version for v-ray 2 in this path:
C:\Users\[your computer name]\AppData\Local\Autodesk\3dsMax\2014 - 64bit\ENU
and re-installing the vray 3
Thanks for help.
I have 3Ds max 2014 64bit and new vray 3.0.
I'm trying to install the vray but I have this error message:
" an error occurred during the installation.
Do you want to undo changes made to your system? "