Solved windows 7's inbuilt backup facility - is it incremental?

[Syncopator]

Or does it write a completely new image every time it runs?

The external hard drive I am using has a capacity of a litle under 500MB. I had copied all my important files to it before I started using the automatic imaging.

The backup has two folders, one named WINDOWS 7, the properties of which are Size 0 bytes, Size on disk 0 bytes, Contains 0 Files, 0 Folders.

The other is named WindowsImageBackup and its properties are Size and Size on disk 114GB, Contains 16 Files, 4 Folders.

The system now tells me that there is insuficient space on it to continue writing more.

Which leads me to the question in the post's title and first line.

Do I have to remove some of my files?

 

[SIW2]

It is differential. Older blocks are moved into shadow storage.

Sounds like you haven't got enough space in shadow storage.

 

[Syncopator]

Thank you SIW2, but what is "shadow" storage?

 

[mjf]

Windows uses vhd files and difference imaging described here
https://technet.microsoft.com/en-us/library/dd440865(WS.10).aspx
The shadow copy service is described here
https://technet.microsoft.com/en-us/library/ee923636(v=ws.10).aspx

You can decide not to use the difference imaging by not including images in your backup schedule but make them in a one off fashion using the "Create a system image" in the backup and restore panel. This creates a folder [WindowsImageBackup]. Relying on shadow storage for the difference imaging is not reliable IMO.
To create a new image rename this folder before making another image. If the renamed folder is changed back to [WindowsImageBackup] then this is the image that will be restored. See the tutorials on this forum.

Windows inbuilt imaging has worked fine for me but software like (free) Macrium Reflect is far superior.

 

[Syncopator]

Thank you mjf. That information is very useful.