I use portable apps on my Windows machine whenever possible. One of the issues I have encountered is that portable browsers (Chrome portable, Firefox portable, etc.) cannot set themselves as the default browser on my machine. So, anytime I open a link from Outlook, for example, it opens in Internet Explorer. I finally got tired of it and went looking for a solution. I found ChangeDefaultBrowser : It is a very small app which will make all necessary the registry changes. Ironically, it is not portable, but it beats making the registry changes yourself each time you want to switch defaults. I've only used it once, but so far, it seems great.