Is AppData now the 'correct' place to install user-specific apps (which modify their own data)?

Question

I\'m probably just being very thick here, but it\'s not clear to me where I\'m supposed to install \'new\' user-specific programs on Windows 7 (and presumably Vista too,

Answer 1

Windows 7 folder structure is deeply inspired on Unix structure:

/usr/ -> C:\Program Files\ -> binaries: executables and dynamically linked
/etc/ -> C:\ProgramData\ -> global settings
/home/ -> C:\Users\ -> a folder for each user
~/.* -> C:\Users\Hikari\AppData\Roaming\ -> settings for each user

Windows has more folder, like My Documents for files with content produced by user, AppData Local and Roaming (which Unix usually handles with NFS).

It's about time for us developers to start using these structures. We must separate at least binary files that don't need to be replicated, global and user settings.

When a setup is installing an app, this setup should expect to have permission to write on Program Files. Once the setup is finished, Program Files should be writable only for other setups aiming to update binaries to other versions.

Answer 2

My opinion, for what it's worth, is that user-specific program files is just asking for trouble and is a damn stupid thing to do.

A much more sensible approach is to install different versions of your program to:

\Program Files\Your Program\Program_v0.1\Program.exe
\Program Files\Your Program\Program_v0.2\Program.exe
\Program Files\Your Program\Program_v0.3\Program.exe
\Program Files\Your Program\Program_v0.4\Program.exe

I would then place a bootstrapping launcher at:

\Program Files\Your Program\ProgramLauncher.exe

Then, the user application data folder will only contain data, including an INI/XML/Settings file that indicates the version of the program that this user is working with.

Such an approach satisfies the core tenant of keeping data and executing code separate, allows every user to run a specific version of the code, and offers a small amount of de-duplication by ensuring the same executable code is not copied multiple times across user folders.

Otherwise, go right ahead with installing programs to AppData and undoing the years it has taken us to achieve clean separation of code and data. I found this thread because I noticed that Chromium and DropBox are installing code to AppData. I'm going to uninstall those program, and change the permissions on my AppData folder to exclude execution to ensure I can easily spot other programs attempting the same BS.

Answer 3

Not really.

The directory that serves as a common repository for application-specific data for the current roaming user.

AppData is, surprisingly, for application data, not for installation (Click Once/Silverlight applications aside). You can, and should still install into Program Files, just don't expect to write into that folder.

You can install software into AppData if you want it to follow a user about in an Active Directory environment, which happens if you put it in AppData\Roaming (the SpecialFolder.ApplicationData location).

You can also install into AppData if you want the software to be available to just the user that installs it. This can be useful if, for example, you have multiple users on the same machine, who all want to run different versions of the software in complete isolation.

If you want settings to only apply on the local machine then you use AppData\Local, which is SpecialFolders.LocalApplicationData - this will make AD administrators very happy as the roaming profile size won't suddenly jump up 50Mb or whatever the size of your software is.

If you wanted to create settings which apply to all users then you're looking at SpecialFolders.CommonApplicationData

You should remember never to rely on the actual name of the directory - localisation issues mean this can change and the location does change with OS versions two. You should be using the special folder enumeration in your software, or the equivalent in your installer.

Could you not install into Program Files, but use AppData as it's supposed to be used, and store your database in there?

Answer 4

Windows 7 added the FOLDERID_UserProgramFiles known folder and by default this maps to %LOCALAPPDATA%\Programs. This is used by MSI when ALLUSERS=2 & MSIINSTALLPERUSER=1.

On Vista and earlier there is no canonical per-user application folder but just using %LOCALAPPDATA% is pretty common. Sadly MSI will just use %ProgramFiles% on these systems.

Answer 5

Please install executable files to the %programfiles% folder in Windows - a simple MSI based install package can perform an active setup for any new user who logs onto the machine to create the user specific files and folders in their profiles %appdata% folder. You see this behaviour for Internet Explorer, Adobe reader, etc. - It's the little MSI installer window that pops up the first time you log onto a machine which has those applications installed. - Thanks - a system admin :)

Answer 6

It's 2019, and I just installed Visual Studio Code (a Microsoft product) in the default folder of

%userprofile%\AppData\Local\Programs\Microsoft VS Code

This is probably for getting around the requirement to have an administrator or UAC prompt authorise the installation