Why don't installed programs show up for all users?

The difference between installing for all users and installing for the current user only typically boils down to where the setup program places the shortcuts for the program, where it places any directories or support files, and possibly where within the registry it places program settings. It all depends on the specific program being installed (hence the "maybe"), and some programs will have more differences, and some will have fewer.

For example, if you take a look at "c:\documents and settings" on your Windows XP installation, you'll see at least two directories: one with your user name, and one with the name "All Users". Dig a little deeper, and you'll see a "Start Menu" item beneath each of those. The start menu you see is the result of Windows displaying the contents of both of those: the contents of "c:\documents and settings\all users\start menu" and "c:\documents and settings\--your user name--\start menu" are merged and displayed as the system start menu. So if a program's shortcut appears in the "all users" portion, then it'll show up for everyone. If it's only in one specific user name, then only that user will see the shortcut. Similar, though not identical, concepts apply to the registry and other items in within "documents and settings".

The point of all that is that when a program is installed, it needs to decide where to put its information: either in "all users", or in a user specific section. Sometimes it asks, sometimes it assumes, and sometimes it assumes wrong.

So, what to do? If you're logged in as user "A", and want to access programs that are only visible to user "B", here are some ideas to try:

• Re-install the program, and, for programs that do so, select "All Users" when it asks whom to make the program available to. You might need to be logged in as administrator to make this work, and you might need to uninstall it first (after backing up any data you might need to preserve, of course).
• Install the program as user "A". Some setup programs are smart enough to realize that they're already installed for another user, and will simply then add the appropriate settings for the current user.
• Copy a shortcut from user "B". For example, user "B" will probably have a shortcut to the program in their start menu:
  "c:\documents and settings\B\start menu\programs\application name\shortcut". Copy that shortcut to an equivalant position in user A's menu:
  "c:\documents and settings\A\start menu\programs\application name\shortcut".
• Manually add a shortcut to the program. This actually works in a surprising number of cases, mostly smaller programs and utilities. Locate the installed program (for example somewhere in "c:\program files" might be a directory for the application, and within that, the ".exe" that is the application), and create a shortcut to that program on your start menu.
• Create another user, "C" and use that. Some programs simply cannot be used by multiple users. It's infrequent, but it happens. So uninstall it (again, after preserving any data you need to save), and then create a third user that users "A" and "B" can share to use the program. Yes, it's a pain, because they'll have to log out, or switch users, in order to access the program. But it's better than nothing. Sort of.

Unfortunately, these ideas will not work for all programs. For example, manually creating or copying a shortcut may bypass additional setup steps that some applications require.

The reason that there's no blanket answer is that setting up an application can be fairly complex, and it really is up to the manufacturers of the specific applications to "do the right thing". Not only is "the right thing" subject to interpretation, many don't do it even when it is clear. So a final suggestion is, of course, to contact the manufacturer of the package you're having issues with and ask if they have a recommended approach to the issue.