(I presume you can get access, I am just being thorough. This page is powered by a knowledgeable community that helps you make an informed decision. 'Free' is the primary reason people pick Inno setup over the competition. Of course, to make an 'All users' install Windows will require administrator access - if you can't get such access (via the usual dialog) then don't bother have someone who can get administrator access install it for you. Inno setup, Advanced Installer, and Windows Remix are probably your best bets out of the 15 options considered. (If asked, leave your profile/settings so that the new install will find them when you run Opera under your account.) it might be a good idea to uninstall the previous version first, so that you don't get confused by the two different copies.
If you have a previous install which is not 'All users' then it will not overwrite that install (as it is in a different location). If you select 'All users', the default install directory will be C:\Program Files\Opera Software\ (or the equivalent given your locale - Windows changes it based on your language). Chapters:00:00 Introduction00:20 Locate drive that your operating system is installed on00:34 Locate user account that you want to change permissions for00:5. You will have choices for type of install (All users, single user, or standalone), install location, etc.