So I have this odd problem, external HDD actually full but shows empty everywhere. What should I do?

[fergzlz]

So I have an external Lacie Rugged Diskt 1tb. There's two partitions in the disk. One of them is 880Gb and the other 120, or something like that.
The real problem is that I have a very important work backup there and all the HDD analyzers show the drive as empty, but when I access it, it is actually almost full and I can look at all the files. I'm worried that my system will see this as empty space and start replacing important data. Any advice?

Some screen captures:
Here you can see in the section "About this mac"

Capacidad = Capacity, Espacio libre = free space, espacio utilizado =used space

in another example:

So here we can see graphically that is mostly empty except for the fact that if we add the numbers in audio, videos, photos we have almost 600gb used but the graphic shows just about 40 gb used.

For further example here is a screen capture of one of the biggest backups:

WTF, I need some help I don't want to accidentaly overwrite something.

 

[monokakata]

What do you see when you choose it in Finder, right-click, and choose "Get Info" (perhaps "conseguir información")? You can also try "Get Info" on folders within the drive.

 

[MacUser09]

If you have another drive, it might be worth transferring your data across and then reformatting the original.

 

[Fishrrman]

Agreed with MacUser09 above.

Time to get your most important data OFF the drive, at least for now.

Then, re-initialize it and partition if required.

Then, TEST each partition in Disk Utility by using the "repair" button.

If you get a good report, REPEAT THE TEST 5 or 6 times in succession.

You want to see a good report for each and every re-test.

If the drive comes up good, I'd begin using it again...

 

[dwig]

Two points:

1. I totally agree with MacUser09 and Fishrrman.
2. This is not a true "backup" if this is your only copy of the files. If the files are truly important then you need at least 2 copies of the files, if not a 3rd.