Either cant complete download or cant find it

Hello,

Ok, I've had this problem for a while now, I thought it was just a virus or something minor that I would fix when I actually had time. Now I have time and there's some stuff that I need to download. For the last couple months now I've been having a problem downloading files on the internet. It seems like everytime it hits about 99%, it either cancels itself or the file gets deleted right away.

I've tried saving the file to my desktop so that its easier to look for, but instead of asking me to open the folder or open the file that I saved, the dialog box just dissapears and my download never completes. What's going on here! I read another thread about this on this forum, but it seems that everyone says the problem is AVG but I dont use AVG, I use trend micro. So I uninstalled Trend Micro and guess what, Trend Micro wasnt the problem because I still couldnt download stuff. Now my Trend Micro internet security can only be installed again by downloading the installation file on the internet and I cant download it because of my current situation!

Now I'm left with this downloading problem and no internet security. I have a feeling the problem is windows defender... However, I dont see it on the program list when I try to uninstall.

Anyone know how to uninstall Windows Defender??


I use:
Windows Vista (Yea I know it sucks, but I havent encountered any problems with it other than this one.)
Internet Explorer
Trend Micro Internet Security
Windows Defender