On my computer that I'm now using for new Vegas i have windows 7 but don't have winRAR. Can i still download mods off the nexus or do i need winRAR. I tried downloading DarNified but it said windows cannot save/open this file or something like that. I downloaded FoMM and NVSE fine. Or could i get the trial for winRAR and download all the mods i want and get rid of it? Thanks, k9000.

WinRar or 7Zip will do. I believe there may be a few mods that require one or the other (NMC's FO3 texture pack comes to mind)

http://www.win-rar.com/download.html
http://www.7-zip.org/download.html

Whats the difference between downloading and buying winRAR from that link? is the download the trial version?

Unless it's changed in recent times, the trial version of WinRAR has a nag-screen but isn't limited in any (significant?) way. My recommendation would be to just go for 7-zip, though; I find it to be better than WinRAR in a number of ways - and it's free/open-source.

hmm. might try that. thanks for your help guys.

WinRAR is literally awful. Use 7zip. Better, more features, no annoying ads, more user friendly, better.