I just installed VirtualBox 4.2.6 on Fedora 17 and faced an error with an alert message below :
Kernel driver not installed (rc=-1908)
The VirtualBox Linux kernel driver (vboxdrv) is either not loaded or there is a permission problem with /dev/vboxdrv. Please reinstall the kernel module by executing
as root. If it is available in your distribution, you should install the DKMS package first. This package keeps track of Linux kernel changes and recompiles the vboxdrv kernel module if necessary.
for your information I’m using fedora 17 with 64 Bit system, the problem solved by installing some dependency packages, try this to resolve the problem
yum update then yum install binutils gcc make patch libgomp glibc-headers glibc-devel kernel-headers kernel-PAE-devel dkms