In this tutorial I will upgrade the kali linux 3.7 kernel to the 3.12 kernel, the reason I upgraded the kernel is because an error occurred when running virtualbox on my kali linux. after playing around on google it turns out that virtualbox requires linux-headers, and it turns out that there is still another problem when you want to install linux-headers, the problem is that in the kali linux repository there is no linux-headers package for kernel version 3.7, so you don’t want to have to install it new kernels.
Enough of the story, now I will tell you step by step how to install the kernel via synaptic

dpkg –list | grep linux-image

in the picture above is a list of installed kernels
so now we start to install the new kernel.
1. open synaptic on the Application menu>> System tools>> Administration> Synaptic Package Mnanager
or just type in terminal

synaptic

2. after synaptic appears, search for linux-image-3.12, for that 32bit choose i386 for 64bit choose amd64
then right click select mark for installation

3.click apply

4. A confirmation message will appear, then click apply again, wait for the download and install process to complete

5. After the install process is complete, we check again to make sure the new kernel has not been installed

dpkg –list | grep linux-image

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