Windows activated in bootcamp but not on Vm Ware Fusion

if you have 1 windows key Microsoft only let you activate it on one platform

I would contact Microsoft and or VMware fusion about your options

it refuse to activate because it view bootcamp as 1 machine and VMware as another and ms don't want you to install their os on more machines then you have licenses for

What did you do, install Windows twice, once in Boot Camp and once in the VM?

I had this setup and had absolutely no problem since Windows is only installed once, using Boot Camp. In your VM you only point to the Boot Camp installation of Windows you do not install it again. Windows is then only installed once therefore only requiring one license. This configuration, including activation is explained on the Parallels and Fusion sites.

What is the version of Fusion? If the BC/Windows was activated first, under Fusion, the hardware signature is different. In older versions of Fusion, re-activation of an already-activated BC/Windows worked correctly.