Asus eee pc 1215b dual boot (debian and windows), downgrade windows 10 to windows 7 pro x64

the disk of system used mbr/dos partition. there are 2 option to install windows 7 pro:

1. using usb and rufus in mbr mode
2. using cd/dvd rom

for systen with mbr/dos partition, using cd/dvd is easier. 

the installation is straight forward. yoy format c:/ contains windows 10 , and select this disk as target your windows 7 pro x64. it takes 30 minutes to insta windows 7 pro x64 from dvd.

you need to install driver for vga, wifi and usb. my system uses broadcom bcm4313 combo bluetooth. drives is not exist in official website for asus eee pc 1215b, but exis asus support. alternative, downloas bcm4313 from windowa catalog. you can uses your existing debian to download driver after you repair grub boot.

to repair your existinf grub follow these steps:

1. boot from any debian media 
2. enter rescue mode, debian will load any components require.
3. choose your root system 
4. choose execute a shell 
5. run 

# grub-install /dev/sda/
# update-grub


after you restart to your syatem and find no windows option at grub screen, enter into your debian. then at root shell execute 

# update-grub

microsoft has closed any support to windows 7, click on windows update will useless.

Note: your internet explorer will rejected by seach engine because it is too old. the option is using supermium browser.

open your internel explorer and type https://www.supermium.net/. download and install it. dont use internet to open or search supermium, the most search engine server will reject your internet explorer.

if you are not sure about supermium security, use your debian 13 with icewn to browse sensitive application like email or banking.