Windows Backup fails with 0x80070002: "The system cannot find the file specified"

I finally figured out the problem. The hidden system reserved partition contains boot configuration data (BCD). Unfortunately, this partition was offline and so was inaccessible. This caused Windows Backup to fail with the symptoms I originally described. However, other parts of Windows are affected, too.

How this happened: I installed 3rd-party disk partitioning software to shrink the size of the system reserved partition and then enlarge the main partition. I then uninstalled that software. I believe it was after this was done that Windows Backup ceased to function.

The problem is described very well here: System Partition goes offline on Windows Server 2008 and Windows server 2008 R2 after installing some 3rd Party Disk or Storage Management Software. My solution was to turn on automount and then rebooting as described in this MSKB article. It is not necessary to give the system reserved partition a drive letter - you just want to turn on automounting and reboot.

While you are checking, you should be sure that the system reserved partition is also the active partition. This fixed the problem for some users (although for me, it was already active and the problem was simply that it was offline).

Other symptoms of this problem - all stemming from the fact that the partition is offline:

• bcdedit fails with the error "The system cannot find the file specified" when you run it from an elevated command prompt.
• bcdboot doesn't work either.
• msconfig's Boot tab is empty and non-functional.
• You get errors when rebooting from BitLocker-Driver in the Advanced Event Log, complaining that Encrypted volume check: Volume information on \\?\Volume<volumeID> cannot be read. - even if you don't use BitLocker or have Windows 7 Ultimate.
• The list of operating systems in the System Control Panel's Advanced tab is empty.
• Viewing the partition from Disk Management doesn't show the file system type or volume label for the system reserved partition.
• Windows Backup fails with 0x80070002.

Note that there are many other reasons for why Windows Backup fails with 0x80070002 - the error reporting in this product is extremely bad. It would be extremely helpful if Windows Backup would so much as even emit a verbose log file describing what it does.

What tipped me off to this investigation in regards to my BCD configuration was some discussions on Microsoft TechNet at http://social.technet.microsoft.com/Forums/en-US/windowsbackup/thread/5e9150e6-809b-4e2a-9360-55567678a9e3. In particular Sneha from Microsoft notes 5 common causes to this issue:

Regret the inconvenience caused. The different causes for 80070002 error that we have seen so far are:

1. USB controller issue for target connected via USB (Not an issue in your case)
2. Machine has a dual boot configuration with Linux and uses Grub2 bootloader.
3. Backup happens to a network target over a wireless connection with disconnects.
4. Snapshot on the source volume gets deleted while the backup is in progress due to very little shadow copy storage area on the source. Type 'vssadmin list shadowstorage' from an elevated command prompt and have a look at the Maximum shadow copy storage space for the source volume included.
5. The source volume has disk errors (which is most probably not your scenario since running chkdsk has not solved the problem for you)

Cause #2 caught my eye and made me wonder "is something wrong with my boot setup?"

If you use the System Restore feature in Windows to create automatic restore points on your drives, this may be the cause of your Backup failure. After trying many other solutions, my problem was resolved by deleting all of the shadow copies (i.e. restore points) that are created by the Windows System Restore feature. Apparently I did not have enough free space to allow the Backup Utility to do its thing. Be aware that following my procedure below will delete all of your System Restore points, however, new ones will be created.

1. Click on the Windows Start button and select Control Panel.
2. Double-click on the System icon.
3. Select System Protection from the left menu to open the System Properties dialog box.
4. Click on the System Protection tab.
5. At the bottom of the page, there is a Delete button (or similar). The description instructs that it will delete all existing restore points.
6. Click this button. When prompted, confirm the decision.
7. Try running Windows Backup again. If it works, go back and create new restore points (if desired) in the System Properties dialog box.