How to backup Windows 7 and revert upgrade to Windows 8

Solution 1:

You can use the free utility from Microsoft: Disk2vhd that will create a virtual image of the running OS. Alternatively, you can use the built-in Windows 7 utilities to achieve the same effect (the VHD file is saved in <target drive>\WindowsImageBackup\<computer name>\Backup <date and time>\). You can then:

• restore this image to the partition it came from using Windows installation DVD
• boot your old Windows 7 installation from the VHD file (!!!) - using the bcdboot command
• mount this partition as a drive in running Windows 8 (e.g. to copy some files from it to Windows 8) - using Control Panel -> Administrative Tools -> Computer Management -> Disk Management

If it so happens that you need to restore only some files, the easiest way is to mount the VHD image as a drive in Windows 8. If, however, you would like to restore the whole partition, you can follow the Restore your computer from a system image backup article (basically, boot Windows 7 installation DVD and choose System Image Recovery option). If this fails (and it did for me once, because my SDD failed and I replaced it with a tiny bit smaller one and Windows couldn't cope with that), you can use a 30-day trial of Acronis TrueImage for this task. It's the best backup/recovery tool I know. Just follow the Restoring Windows 7 VHD Backup Files with Acronis True Image Home tutorial.

EDIT:

Backup Requirements: if the partition you wish to backup has XX GB used space, you'll need at least XX GB of space on the drive you want to save the VHD file to. The size of the whole partition doesn't really matter, only how much space is actually used on it does. If you want to reduce the required space, you can move some non-application files (movies, photos, etc.) to a different drive before backing up. There's a handy tool called WinDirStat that will show you where your disk space is wasted.

Also, all software used here is free. Well, Acronis only for 30 days, but you'll install it just before deleting the whole partition anyway :)

Solution 2:

The built in backup utility should let you restore from a Windows 7 install disk or a system repair disk.

I personally use a third party utility that should work as well. Clonezilla or Macrium Reflect Free is what I use. Clonezilla is nice since it runs independantly of the base OS so is nicer for unusual situations, like when you have 5 different OSes on a drive. Macrium reflect has a better compression ratio for windows drives in my experience and only backs up the space used. Considering that different sorts of data have different compressibility I'd be lying if i gave you exact numbers. It really depends

Always test restoring your backups before doing anything particularly risky.If this isn't plausible at the very least ensure that your recovery disks work, and can see the drive you have your backups on - in some cases you'd have to go for an alternate build with better hardware support.

I personally tend to do a file level copy out of personal files (things like videos and music compress VERY badly, so copying out your user files is a good idea), then do a system level backup without those files. YMMV