Default Flastool isnt working!

So ive got the firmware i want, in the firmware file in my C drive

I click the flash button get it ready, I then connect my phone to the computer in flashmode and it doesnt do anything

so i click the flash button again and then select the firmware, then hit flash and it says this

02/058/2014 11:58:32 - ERROR - Cannot delete C:\Flashtool\.\firmwares\prepared\system.sin
02/058/2014 11:58:32 - INFO - Cannot open bundle. Flash operation canceled


what am i doing wrong!