Tuesday, November 10, 2009 9:39 AMHi,
My C: drive has 355GB used out of 931GB and my D: drive (a physically separate drive) has 465GB free out of 465GB. When I try to do a backup from C: > D: using Windows 7 backup it spends hours doing it and then fails telling me there is insufficient disk space. FYI - I am setting my own backup (i.e. choosing what to backup myself), excluding some libraries, and including a system image.
For a start I'd expect Win 7 to identify that there isn't enough space prior to attempting a backup although I can't understand why it is failing anyway when there appears to be ample space. Why is this not working?
Wednesday, November 11, 2009 5:54 AMOwnerHi Phil,
Thanks for trying out Windows Backup.
Windows Backup in Windows7 allows both file backup & system image backup to be taken as part of same scheduled backup. However we are still taking two separate backups. So the space required for backup would be the space required for file backup + system image backup. If you open space management UI (click on "Manage Space" from Backup & Restore Center), you can see the space utilized by file backup & system image backup separately.
It is not possible to estimate the size of file backup upfront as the backup is getting compressed.
In case of system image backup, we could provide a size estimation but it can only be an approximation. Since we take backup to VHD, the size estimation needs to include VHD format overhead. Also the previous versions of system image backups are stored in shadow copies. So the size estimation needs to be aware of how much of churn the backup would incur to be able to come up with the right number. This is not possible to estimate upfront.
Hope that clarifies your concerns.
Wednesday, November 11, 2009 7:45 PMSriram,
Thanks for the response it's very helpful. That makes perfect sense, for some reason I hadn't realised that the system image was more than just the OS and that it included the user files too. Now that I realise two backups are taking place at the same time it makes sense that there is insufficient disk space.
Friday, January 01, 2010 4:48 PMSriram,
I understand that it is difficult to predict how much space would be required for a backup, but do you think a 10GB partition is reasonable for a backup disk? Win7 won't even start my backup, claiming that there is no space available on a totally free drive.
Saturday, July 17, 2010 12:31 AM
I've had this problem, I have plenty of spare disk space but kept getting the back up failed insufficient space error.
The cause and solution....
System reserved partition didn't have enough free space to create the back up image temp files so I shrank the C: partition by 500mb, created new partition of 500mb and labelled it as active, restart with win 7 DVD and select start up repair ran it twice to create new MBR etc. When this is done and win 7 is starting witout any issues delete system reserved partition. Image backup has worked without a problem ever since.
100mb may be more than enough to create a boot and recovery partiition but it doesn't allow enough space for the image backup temp files to be created.
Friday, September 03, 2010 4:10 AMI was backing up on a separate external disk, back up only goes up to 30% of hard disk then abandons. This is documented that it does take only 30% of hard disk to backup then says insufficient disk space. I want Windows 7 to back up using the entire external hard disk. How do I set that?
Monday, April 18, 2011 4:08 PMI have a dedicated hard disk for backup, and I'd also like it to use more than 30%. Is there a registry entry or something than can be changed to increase it?
Thursday, April 12, 2012 7:08 PM
Based on your explanation, does that mean I could only do a system image backup if all I want to do is replace my hard drive?
I ask because my external hdd is not sufficient in size also for both but all I need to do is replace my hard drive on my laptop.
Thursday, April 12, 2012 7:12 PM
Wednesday, July 25, 2012 12:52 PM
100% copy of the computer as it sits, all files all settings, this is great if you have an up to date image backup, and the hard drive fails, just replace the hard drive, boot the computer from the special cd (that can be created from any windows 7 computer, from the backup program) select the option to restore computer from image, select the correct image by date, if there is more than one (if you use the same external hard drive on more than one computer, you WILL need to know the correct computer name, so that you can select the correct image). I have restored several computers that the user had over 40GB of data, and the compete restore only took about 45 minutes..
this makes a backup of data files that are located in "My Documents" and maybe some other locations, if you have programs that are NOT saving the data files in my documents, you may want to add that directory to the backup, or reconfigure the program to save in My Documents. Depending on the size of the drive that you are backing up to, the file backup will keep multiple copys of "different versions" of files (files that you have changed since the last backup). If for some reason you have a file that becomes corrupt, deleted, or made changes that you decided were wrong, you can restore an old copy of just that file. It runns what they call a "shadow copy" (you can goole that for more information)
Just remember one thing, If you have your drive split into two different partitions, and you are backing up C: to the D: drive, if the drive fails, you will loose BOTH C: and D:, so you SHOULD be running the backup to an external drive.
I recommend that your external drive be two-three times the size of the drive that you are backing up, so that it has the space needed to keep more than one copy of the Image and Data file backups. With backups it's always nice to have an option B when you find out that option A also doesn't work.
I setup Windows 7 backup on every single computer that I can.
- Edited by Adam_Carter Wednesday, July 25, 2012 12:54 PM
Sunday, December 23, 2012 12:21 AM
I too am having the same problem, where after several hours I am told the backup failed due to lack of space. The drive I'm backing up contains about 500 GB and the drive I'm backing up to has about 1.6 TB free. I selected the option to let Windows select the files for the backup.
After it fails I go to the Manage Space link, and I see the following...
Data file backup: 195.59 GB
System image: 0 bytes
Other Files: 211.81 GB
Free Space: 142 TB
Total Size 1.82 TB
Where's the problem?