huge DnF problem

every single time I play Dunpa at different times for NO reason Windows Vista will pop up saying "the publisher cannot be verified" for the 7z.exe file under users/locallow/dnf/

How in gods name do I stop this? I've tried every single thing possible using Internet Explorer, searched literally for hours of google trying different methods, I've deleted the file and it comes back, I've disabled windows from actually running it and for some reason it STILL crashes my computer. What is this file and why won't it leave me alone? It has unknown publisher so I can't just click always trust it...and if I did, whether I click cancel or run, Dunpa crashes and it thinks I've died...huge problem when you are about to finish a King run and you get kicked out while you're at full health.

ANY help would be greatly appreciated...

As I mentioned, running Windows Vista Home Premium I think? So I can run that pgedit.msc file or whatever that everyone recommends and I've tried editting the registry and even adding lines to enable *.exe that line was never there initially so I don't know if I added it right...and even then, this exe kills Dunpa and closes it down...

That's what I figured it was because my best friend was spamming her Mage and she kept getting the bot check to appear and then after the most recent update it started to happen...thank god it's not only me. The best temporary fix I've found for now is edit the properties for the file and deny it from being executed (if you are using the administrative access) and it seems to delay it longer than normal. I'll try the recommended patch method though once I get home, thanks for all the info so far.

For me it happens in the boss room while I'm doing King runs solo which involves a lot of spamming of skill to kill the initial mob, which is why I started to suspect maybe it was that.