Problems downloading

[Kristoffer]

Hi out there. I have a Mac which has run smoothly for a long time. Now, and for a while now I have troubles downloading different programs. It seems as though a firewall is installed though I have set the settings to "allow all incoming connections". I can see that some firewall activity though I haven´t put up any. I have contacted my network provider and they say that it is not from there part. It´s impossible for me to get applications such as team viewer, onyx, voddler net, speed downloader.
It makes it very difficult to give my mac a proper cleaning if that is the issue when I can´t get the software to do it. I have even tried to get the software via dropbox. Same story. By the way I´m from Denmark.

Can someone help. Kristoffer