unusable memory stick

[#1]

Hi
I went to a seminar yesterday, and all the presentations were provided on a 2Gb memory stick.  All very nice.  I've now copied the presentations on to my computer, where they'll be very useful.
I then tried to delete them off the memory stick, but they won't delete.  Tried to reformat the drive - won't format.  On looking at the disk on Windows, it has a size of about 1.8Gb,
Can't delete the partition.  On top of that, actually reading the stick is very slow, and if it's plugged in, I keep getting delayed write failed messages, even if I'm not actually reading or writing to the stick. I can't write to the disk either. (There doesn't seem to be a write protect switch either - so it's not that)
It's only a 2Gb stick, so its not a big deal, but I'm intrigued as to how they did it, and if it can be undone.
Any ideas?
John

[#2]

http://www.mediacopy.co.uk/USB_flash_read_only.htm

[#3]

If that is similar to the Sandisk U3 mechanism then you might find that this tool http://u3-tool.sourceforge.net/ will allow you to delete the CD partition on the memory stick and get the space back for normal read/write.

[#4]

Thanks Oldjim - that looks like it, but id so they had them made up very quickly.  I know for a fact that they didn't get one of the presentations until the day before the seminar! I also can't write anything to the stick.  It takes ages, then comes up with an error message.
John

[#5]

the U3 partition file didn't work

[#6]

Oh well, it was worth a try...

[#7]

Of course it could just be a faulty stick 
John

[#8]

It may be protected with a password or some similar thing. If you could use a Linux Live CD to boot into a Linux system you could possibly circumvent the protection. A member of our computer group (a computer dealer) often does this when customers have forgotten their password.  Another way would be to boot "GParted" from a CD and delete the files with that.