Information
SELinux must be enabled at boot time in your grub configuration to ensure that the controls it provides are not overridden.
Error, bootloader not found in the following locations:
/boot/grub/grub.conf
/boot/grub/grub.cfg
/boot/grub/menu.lst
/boot/grub2/grub.conf
/boot/grub2/grub.cfg
/boot/grub2/menu.lst
Solution
For grub based systems edit /boot/grub/menu.lst and remove all instances of selinux=0 and enforcing=0 on all kernel lines.
For grub2 based systems edit /etc/default/grub and remove all instances of selinux=0 and enforcing=0 from all CMDLINE_LINUX parameters:
GRUB_CMDLINE_LINUX_DEFAULT='quiet'
GRUB_CMDLINE_LINUX=''
Run the following command to update the grub2 configuration: # update-grub