Error when removing files from passport

I am trying to delete some files that are on my Passport.  1. They will not deleted constantly telling me some files have to long names for the recycle bin.  or that the file name has been changed or deleted when we didnt change anything Have installed Pointless Dmailer software.  I have tried to delete it copy files so I can format nothing is working.  What do I do??? Considering buying a different brand of External Harddrive as this one is causing so many problems

My Passport Essential is the product type.