Space on pendrive is used but I can’t see anything.

So my girl recently brought me her pendrive to check it out and I noticed that there’s 4,5GB used on it. When I select all the folders there it sums up to only 1GB. I’ve checked for hidden files, and also for hidden system files. What happened to the 3,5gb that is supposedly being used ?
Answer #1
You can always move the data to a folder in your hard drive…Quick format..Problem solved…
Answer #2
empty the recycle bin
or format it
Answer #3
you may have hidden file just format it its the most painless way
Answer #4
thanks for help, I wanted to format it, but was wondering if there is any way to find out what exactly takes up the damn space
Answer #5
thanks for help, I wanted to format it, but was wondering if there is any way to find out what exactly takes up the damn space
viruses ^_^ also if shes 1337 she could have hidden her pron on there. if your GF like pron. which is a plus i guess…? depends on which type XD