Solution 1:

I realize this thread is old, but for those who are still wondering:

Open the Registry Editor (search for regedit in the start menu), then open HKEY_CLASSES_ROOT\http\shell\open\command

Double click on (Default) in the right pane, then delete what is in the "value data" field and replace it with "" then click ok.

Then go to HKEY_CLASSES_ROOT\https\shell\open\command, double click (Default) and replace whatever is in the box with "" again and click ok.

Solution 2:

This is quite easy. Just rename firefox.exe to zfirefox.exe and it's done. (or any other browser that you might have) Obviously, you'll want to update any shortcuts and firewall rules.