Flash Drive (Memory stick) not working properly. Cannot format it or delete files

What is a Linux box? Help me here.

Scottcha, thanks for your post. You have to forgive me as I am a pensioner (senior) and am not always up to speed - although I am very persistent. I m always curious to see how things work and have done a lot of electronics over the years. In any case, you will have to talk me through your post a little more before I'll know what to do.
 Can you give me a step by step?  (for me it is not a question of tossing the item and purchasing another - I can afford that - but one of curiosity). I'm Irish

Eamon, did you test the problem on another PC yet?

Yes I tested with another PC and same problem. Its looking like 'unusable', but I'll try the other advice before binning it.

Tried various suggestions without success. I cannot create files and transfer them onto the flash drive.  When I run 'diskpart' and 'list file' the flash drive does not appear on the list.
In the CMD screen I have changed the opening screen to the flash drive (Drive I) and then run the format command. It appears to carry out the format down to the last second when an error message appears, saying the format cannot be completed. It says the the flash drive is 'unusable'.
So I'm calling it a day on this one. Thanks for ideas and help. They will be useful later, I'm sure.

did you try the software i listed above, and what were the results?

I love that comment Eamon:  "I'm Irish" ;-)
What you perhaps didn't realise is that you may have inadvertantly insulted a fellow Irishman who posted earlier.  His user name should stick out like a sore thumb to somebody from the same island.

Wow. Now I'm looking. Got it.

Nobus, thanks as always for your help. I did try the various links given by you. So I know the item is unusable.

thanks for the update, EamonX
too bad  the stick is bad (but it happens often)

oh - and don't forget to close this, if no more help is needed

For the step-by-step.

Just download one of the Knoppix or Ubuntu ISO files.

Then follow the steps in my last link.  That will give you the steps to properly burn the ISO so that it is bootable.

Boot from that optical disk.  From within use the utiliites to try to format your flash drive.  Under Knoppix you want to look for a program called gparted.  That will let you create a new file structure if possible.

If this doesn't work then after looking at the above comments it does look like your drive is dead.

But keep these disks as they are good for a variety of troubleshooting other issues.

Did'nt solve the issue. The item is unusable. However it  points someone with a similar issue in the right direction.