Usb Stick Keeps "losing" Files - What's Going On ????

[Gizmonster]

.... so, in a nutshell .... I'm trying to back up some files from my PC.
Approx 16 Gig in total. I tried backing up to a pen drive. I backed it up, checked the drive to make sure everything was there and everything was ok. I "safely removed" the drive .... came back to it at later .... and some of the files have gone. Removed it and tried again and some more have gone.
Anyway, I tried backing up again and it did it again, so I thought it might have been a dodgy pen drive, so I tried it again, this time on to a 32 Gig USB stick.
Eveything is ok at first .... looking at the properties of the USB stick and it says 16 Gig ish. However, I safely remove it, come back to it and some files have gone again. Anyway, I tried again and it's just done the same ..... anyone any ideas what's going on plzzz ????

[Mosaic]

I've experienced this with sticks and with uploading to remote servers - if you (say) copy and paste a large number of files the connection seems to simpply go 'oh soddit they'll never notice' and drop random ones out.
I've found the only secure answer is the long way round ie transfer smaller groups of folders in batches.

[Gizmonster]

I "dragged and dropped" 1 single folder, which contains other folders, which in turn contains other files and folders - approx 16 Gig in total. It takes quite a qhile for them all to be copied across - approx 2-3 hours. Everything seems to have been copied okay, 'cos if I right click and select properties, it says it's approx 16 Gig - which is what it should be.
The problem arises when I take it out and put it back in. For some reason or other, it loses files. The last time I did it, I right clicked and selected properties and there was now only approx 6 Gig in total.

What gives ??

[Old_Geezer]

Difficult to get my head around given it's occurred on 2 different drives. I'd have otherwise thought they were faulty. I am aware cheap ones from internet tat bazaars are not unknown to be 'doctored' so they look bigger than they are; which only comes to light when unexplained failures occur.

[Old_Geezer]

Use on an *EMPTY* drive

http://www.vconsole.com/client/?page=page&id=13

[Gizmonster]

Yea I could understand if it only happened to one, but it's happened to 2 different drives - a pen drive and a USB stick (I'm not sure if there's actually any difference between a pen drive and a USB stick).

...... and it was exactly the same problem both times ......

[bibblebub]

Are you using security software e.g. Norton that is set to automatically scan the memory stick when it is inserted?

[Gizmonster]

As far as Im aware, my anti virus software isn't scanning the drive, etc .... I'm using MSE.

[Gizmonster]

Win XP by the way .... yea I know it's ancient :P