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My system setup is as follows:

C:\ NTFS formatted internal (SSD) boot drive (Windows 7)
D:\ NTFS formatted internal data drive
I:\ exFAT formatted external backup drive

I periodically back up data from D:\ to I:\. I have recently started to use Windows 7 backup to create system images of C:\, but it will not let me create the image directly to I:\ because:

"This drive cannot be used to store because it is not formatted with NTFS"

So instead I create the system image to D:\ and then manually copy it from D:\WindowsImageBackup to I:\WindowsImageBackup, as Administrator.

I am assuming that Windows Backup thinks that any non-NTFS drive is incapable of storing files > 4GB, hence rejects non-NTFS file systems. My question is would the integrity of the image stored on I:\ be maintained i.e. would there be any problems with restoring from the exFAT formatted drive? The only true test would be to attempt to restore from I:\WindowsImageBackup but I don't particularly want to attempt a restore if there are known issues and risks. Furthermore I don't want to have to reformat I:\ as NTFS and recopy all the data over if there isn't really a problem with exFAT.

Experiences appreciated.

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According a Microsoft Answers employee on an official thread, NTFS is required for security purposes, so it's not a file size issue.

I would open Backup and Restore and choose the "Select another backup to restore files from" option and see if you can pick the exFAT drive as a location of files to restore from. If it refuses to "see" your I: drive, you should reformat it as NTFS if you want to use it for backup purposes.


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Unfortunately I cannot pick the exFAT drive through "Select another backup to restore files from" - no devices are displayed. The MS answer seems a bit vague, and doesn't make sense (at least to me!). Thanks for posting! – Jimadine Jan 1 '14 at 15:27
When you select "Select another backup to restore files from" no devices are shown but all other backups are shown. – Hunter Jan 1 '14 at 17:26

What I can tell you is that there is no reason for you to format a hard drive internal or external with the exFat system. Unless your intent is to use it for for multiple OSs. exFat basically is readable and writable by Windows, Mac, and I do believe BSD (Unix based OSs). How ever it is meant for flash-drives. That way there is no need for specific OS type flash-drives, it also has a lower file system overhead. But lacks all the benefits of a NTFS file system.

If I were you I would listen to Windows complaint. Unless you are trying to share and write files between different base OSs I would reformat the external drive to NTFS and then use it for my backups.

If your intent is to use it for backups for windows only then there is absolutely no reason whatsoever to have it formatted as exfat.

Take a look at this comparison chart, NTFS vs FAT vs exFAT, and look under the File System Features section.

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That is a big "unless". Multi-platform is significant. And FAT has great limitations. – pc1oad1etter Jan 7 '14 at 1:24

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