Publisher Unknown message

Hi

When I start to install a copy of Ad-Aware which I've downloaded from Filehippo (the same for CNet) I get a Windows message that the publisher is unknown and it hasn't been digitally signed. Is it safe to proceed?

Thanks for any advice you can offer.

Yes. but if you prefer you can download from Lavasoft webpage

http://www.lavasoftusa.com/

I'd also recommend getting it from Lavasoft's homepage.

When I went to try out Nod32 just the other day that I downloaded from Filehippo.com and when using WinRAR to test the SFX RAR it stated the authenticity was corrupt, thus I didn't install it.