system partition not allowed to be formatted

Your original post mention the System Partition and being formatted.  Not sure exactly what you are doing but a "System" Partition holds the boot files for an install.  Windows won't let you format it..

If you are creating a System Image Backup and are asking about an external drive, the imaging software will usually just create folders on the external drive..

Robert, what are you backing up exactly? 10 GB is not large enough for the see partition which is what you would normally backup along with the necessary system partitions it requires.

Are you doing a file back up? If so what exactly are you wanting to format?

If it's a system image backup then the app you're using should help you create a boot or rescue disk to use in case windows won't start.

HI Robert. I'm Greg, an installation specialist, 10 years awarded Windows MVP, and Volunteer Moderator. If you will work with me I will be here to help until the issue is resolved.

C drive won't allow formatting while it's running. You've not given me enough information to know exactly what you want to do so if these don't cover it please explain more so I can help you better:

If you want to reinstall Windows then follow the gold standard Clean Install in this link which compiles the best possible Install of Windows which will stay that way as long as you stick with the tools and methods given, has zero reported problems, and is better than any amount of money could buy: http://answers.microsoft.com/en-us/windows/wiki...

You can save a System Image backup stored externally so if Windows ever becomes irreparable you can restore C in 20 minutes and be back up and running. Here's the best free imaging app and how to use it: https://www.howtogeek.com/howto/7363/macrium-re...

Macrium will help you create a Rescue disk when you install and run your first image.

You can always create the latest bootable Windows 10 installation media which includes the Repair Console, following the steps in the middle of the download page here: http://windows.microsoft.com/en-us/windows-10/m...

You can also create just the bootable Repair Media here:

http://www.tenforums.com/tutorials/4200-recover....

I hope this helps. Feel free to ask back any questions and keep me posted. If you will wait to choose if I resolved your problem, I will keep working with you until it's resolved.

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