Virtual Box wiill not run error Kernel driver not installed (rc=-1908)

It was running last week but now will not run gives error

Kernel driver not installed (rc=-1908)
The VirtualBox Linux kernel driver is either not loaded or not set up correctly. Please try setting it up again by executing

'/sbin/vboxconfig'

I think it is because the kernel was updated anyway of stepping back to the older kernel?

Thanks for any help.