I am using a raspian stretch and tried to write the image onto a SD card. Whenever the writing process is completed a partition 4gb is formed and the windows prompts me to format it. I am using a 16gb class 10 uhs san disk SD card. The card when inserted into the raspberry pi it does not boots up. I used softwares like etcher,Win32disk Imager,Rufus all with the same results. I tried the sd card on both Raspberry pi Zero as well As raspberry pi 3 model b.....What to do now..?
If you follow the instructions in https://www.raspberrypi.org/documentation/installation/installing-images/README.md it should work in the Pi.
You should verify the SHA-256 checksum BEFORE copying.
Ignore anything Windows says - it can't (actually won't - it could) read Linux partitions.