vi /etc/default/grub 
...
GRUB_DISABLE_OS_PROBER=false

vi /etc/grub.d/30_os-prober
...
      for LINUX in ${LINUXPROBED} ; do
        LROOT="`echo ${LINUX} | cut -d ':' -f 1`"
        LBOOT="`echo ${LINUX} | cut -d ':' -f 2`"
        LLABEL="`echo ${LINUX} | cut -d ':' -f 3 | tr '^' ' '`"
        LKERNEL="`echo ${LINUX} | cut -d ':' -f 4`"
        LINITRD="`echo ${LINUX} | cut -d ':' -f 5 | tr '^' ' '`"
        LPARAMS="`echo ${LINUX} | cut -d ':' -f 6- | tr '^' ' '` consoleblank=180"
...