1TB Ext HD Has 581GB of Data But Only 57GB of Free Space

[danvm]

I have a 1TB external hard drive I use to store images of my computers. It is reporting that I have 56.8GB of 931GB available but there is only 581GB of data on the drive. I've emptied the recycle bin and removed any system files but it still will not show the free space I should have left. Could really use some ideas!

 

[Pauly]

I am guessing you use windows to create a system image backup, if this is the case then the backup files will show as 0 byte even though they are many GBs in actual space.
This is normal behaviour and nothing to worry about, if you absolutely must see the true space add up you simply need to double click into the backup folders (I think there are about 6 or 7 folders per backup) which will issue a prompt saying you don't have permission do you want to continue and after you have opened each folder in turn the backup will reveal their properties and your disk space should return to normal

*Warning*
Windows backup system can be temperamental so I would avoid unnecessary renaming/relocating of backup files/folders as occasionally this can cause problems with windows seeing the image if you need to restore an image at a later date

 

[danvm]

I'm actually using Macrium Reflect to make my images. They detail the space used accurately so I'm rather perplexed over the discrepancy.

 

[Pauly]

There are some good free programs that will give you accurate listings of where the space is being used, a good one is WinDirStat
These type of programs are especially helpful because they can show parts of the disk that is being used by the system for things other than storage eg hyberfile/pagefile etc its worth a look

May also be worth checking your volume shadow copies to see if they are using disk space there

Check disk management with the drive plugged in and make sure has no properties it shouldn't ie not marked as active etc and the partition type is set correctly
Post a screenshot of this if you can

Heres a snip of mine with two internal drives and one external plugged (and yes I know my C & D drives are back to front im just to lazy to swap the sata plugs around )

 

[danvm]

Attached is the screenshot as requested. It would seem all is OK.
Thanks so much for your efforts!

 

[danvm]

Running WinDirStat I found that the Recycle Bin for this drive was using about 300GB of space. I've never noticed an external drive to reflect the capacity WITH what is stored in the Recycle Bin. Just to be on the safe side, I will copy the data to another drive, re-format this external drive., and copy the data back again.

Thanks again for your assistance!

 

[LMiller7]

Windows Explorer has some issues when using folder properties to determine the disk space consumed, as in in post #1. The numbers shown are often lower than they are in reality, possibly in very significant ways.

Windows Explorer runs under the users account and is subject to all of the limitations it may have. There are some folders like "System Volume Information" that by default even an elevated admin level account has no access to. Typically this folder is quite large. In a world where most users use an administrator account by default they really do need to be protected from themselves. The previously mentioned folders contain critical information and careless modification could have disastrous consequences. And when UAC is enabled (the default state in Vista and later) admin level users are effectively running with a standard account most of the time. This imposes even more limitations on Windows Explorer.

When Windows Explorer is going through the folders in a drive (to determine space used) and sees a folder it cannot access it has no way of knowing what it contains. It then does the only thing it can do and reports zero as the size consumed. The inevitable result of the security system at work.

Programs such as WinDirStat get around this problem by using a service running under a system account that has no such limitations. It is able to more accurately determine a folders contents. But in any complex file system like NTFS the determination of the space consumed by a folder is only an approximation at best and complete accuracy is impossible.

Then why doesn't Windows Explorer use such a system? The problem is that most IT managers would consider this an unacceptable security risk because it effectively bypasses NTFS security and allows users to see files they should have no access to. Even seeing the space consumed by such files is often considered an unacceptable risk. Precautions could be set in place but they might be circumvented. That would make Windows a hard sell to the corporate world.

For security reasons things like WinDirStat must remain an add on that can only be installed by an Administrator.

Security always has it's price and that price is paid a a wide variety of ways.

 

[danvm]

"Just out of curiosity, was that a new or old external HDD? And was it formatted (format type?) prior to creating Macrium system image?"

It is a fairly new Seagate 1TB USB3.0 HDD, formatted as NTFS prior to use.