make install Can't read private key

У меня mint 17, при попытке мейк инстала получаю ошибку "Can't read private key"
плиз хелп!!!

ratamahata vloopback # make install
Installing webcamstudio kernel module...
make -C /lib/modules/3.13.0-24-generic/build M=/root/tmp/vloopback modules_install
make[1]: Entering directory `/usr/src/linux-headers-3.13.0-24-generic'
INSTALL /root/tmp/vloopback/webcamstudio.ko
Can't read private key
DEPMOD 3.13.0-24-generic
make[1]: Leaving directory `/usr/src/linux-headers-3.13.0-24-generic'
depmod -a