The mystery of the self replicating file (hopefully) solved!

For the last 7 or so days I have been struggling with a folder that suddenly appeared on one of my USB drives.  I didn't put it there, I didn't give it permission to be there so I was most put out.

The source folder was called qtcurve

So I did what most people would do, I deleted it.  But it came back.  So I deleted it again.  And it came back. Again. So I Googled it so see what caused it.  Google says possibly Linux.  As I'm a Windows XP user who has never even SEEN Linux I say not likely.

So I have to use my memory (not easy for me, my short term memory is TERRIBLE) and try to remember what has been installed or updated recently. Then I remember I've recently updated Quicktime. qtcurve, QuickTime. 

Hmmm, suspect. 
The alarm bells start going off.

So I Google "Is it safe to uninstall Quicktime"?  Turns out its used for  Mov files (pretty much obselete now) and Itunes which I don't use.  So off it goes.  Then the folder comes back.

So I do a more detailed check, bits of Apple software are still lurking.  I uninstall all of them, I've already checked I safely can.
And it STILL comes back. So now I'm thinking virus or spyware.  So I do a search of my main hard drive to see if the folder exists there too.  Several minutes later. 

DING DING DING! We have a match!

It's part of ebook convertor & reader Calibre.
So as a very annoyed person I ask on Facebook how to get rid of the annoying little git.

preferences -> look and feel-> interface style-> default.
According to the very nice and very helpful person on Facebook who I apologise to for sounding sarcastic.  I was literally about to bin my PC at that point.

So I've followed those instructions & hopefully won't be seeing any more of that folder.
If you have the same problem, hopefully this will help you get rid of it quicker than I struggled to.