Recently I updated my Windows PC (which I only use for gaming purpose of course) and managed to screw it. Once I did the planned restart it showed me “No operating system found”. Since I upgraded from Windows 7 to Windows 10 via the update manager I also did not had a Windows 10 image available to recover the system.
Thanks that I still have my Mac, and I am even more thankful, that it understands most of the Unix/Linux commands. So to get back to my old life, I first downloaded the Windows 10 ISO image from the Microsoft Homepage .
Okay so we have an ISO image – how to we get it on an USB stick – a simple copy would not make it. Therefore the following steps are required.
1.) Identify your USB stick – you would not like to replace your data storage or your OS X system.
This I usually do via the mount command:
jvr-mac:~ jvr$ mount /dev/disk1 on / (hfs, local, journaled) devfs on /dev (devfs, local, nobrowse) map -hosts on /net (autofs, nosuid, automounted, nobrowse) map auto_home on /home (autofs, automounted, nobrowse) /dev/disk2s1 on /Volumes/Data (exfat, local, nodev, nosuid, noowners) /dev/disk3s1 on /Volumes/ESD-USB (msdos, local, nodev, nosuid, noowners)
And here we go /dev/disk3s1 is the drive I was searching for. To be sure – double check it in the Finder App.
2.) Convert the .iso image to an .dmg image by using hdiutil
jvr-mac:~ jvr$ hdiutil convert -format UDRW -o Win10.dmg Downloads/Win10_1511_German_x64.iso J_CCSA_X64FRE_DE-DE_DV5 (Apple_UDF : 0) lesen … ........................................................................................................ Dauer: 1m 2.901s Geschwindigkeit: 61.0M Byte/s Ersparnis: 0.0 % created: /Users/jvr/Win10.dmg
The last sentence looks promising!
3.) Unmount the USB stick
jvr-mac:~ jvr$ diskutil umount /dev/disk3s1 Volume ESD-USB on disk3s1 unmounted
4.) Write the image to your USB stick using dd command
This is the most critical part – so be sure that you write the image on the correct drive/stick. Just for your information: if stands for input file, of for output file and bs is the blocksize. The dd command basically copies block by block to the new drive.
jvr-mac:~ jvr$ sudo dd if=Win10.dmg of=/dev/disk3s1 bs=10m
5.) Unmount USB stick again
jvr-mac:~ jvr$ diskutil unmountDisk /dev/disk3s1
And by now you should have a bootable USB stick to recover your system. Lets cross the fingers that everything will work out fine with the PC 🙂