Data multiplying

Hi, 

 

I've been using Norton Zone for a time, and just recently I've suffer a problem with files copying themselves adding the text "_<number>" on its name. It's a problem because some of them get to "_848", which means that I have hundred copies of the same file. 

 

And I mean same file, because some of them where pdf that were never modified, so it can't be a previous version. What is happening? 

 

Kind regards,

Belén.