[Solved] Corrupt files that cannot be deleted and mysterious file extensions

Hi

I noticed that everytime i open up a word document, another one - replica appears on the desktop.Its quite translucent.
Also,i noticed that over time some of my documents have become like that and i cant use them - a file which was named e.i Farming will have been renamed to ~$arming and it will appear translucent and when opened it asks to be converted and once converted the content is something like tonnes of little boxes and numbers.Why does this happen and how do i stop it?Is it a virus?

Also,after reading quite a few answers on many threads i learnt that running Chkdsk and defrag on my drive[external] will fix corrupt files.It did work for like 2 minutes, while deleting files the same error occurred again.Not only that but i realised that some of my files where now inaccessible.WHAT IS THIS THING?..and how do i stop it from continuing?
-- external drive
Moreover, i cut and paste some of these files to my desktop from my external to get rid of them - i seemed to be able to move them to my recycle bin from my desktop,but once in the bin,i still couldnt delete them.I get an error message saying something about : cannot remove <file name>.Directory is not empty.
What is that about??

Is there any good anti virus that can fix this?

Also,is there any antivirus which gets rid of the trojan horse?
I have tried Kaspersky,Norton,AVG,Trend Micro and Avast but to no avail.

Please help.

From Windows Explorer, do not show Hidden Folders and Files.

Grumpy

But i still have the problem with the corrupt files.
One of my folders just got corrupted - just like that, i dont remember having done anything wrong.
Unless short circuiting external drives causes this.
I tried chdsk and defrag on my external but it didnt solve it.
Can anyone help me perhaps?

Also.. is there a virus that causes files to suddenly become unreadable?