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

installationmigrationwindows 7windows-xp

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, though I've not specifically looked at that scenario yet).

Under Windows XP (rightly or wrongly) we always installed our programs into folders under 'Program Files' and accepted that they'd be kind-of available to everyone. From what I can gather under Windows 7 I'm supposed to install my software under the user's AppData folder (possibly AppData\Local\MyApp). That makes a degree of sense, but the fact that this folder is 'hidden' by default means that we're going to have 'fun' talking our users through support stuff.

I want to install our software so that it's user specific (the Users bit in Windows 7 makes perfect sense) but I do want the user to be able to access it if required. Our program also includes a 'data' subdirectory which it needs to write into while it's running (embedded database), but as the program is intended to be single-user/standalone, the data folder being inside a user-specific folder isn't going to be a problem.

My problem is just that whole 'hidden folder' aspect of AppData. As much as I've trawled the MSDN, I can't work out where else I'm supposed to install user-specific programs. Taken one way it would seem to be something like AppData\Local\MyApp, and another way it would seem to be just as valid under the user's My Documents\MyApp equivalent.

Has anyone got a clear guide for where all this stuff goes? I found the MSDN docs confusing. 🙂

Best Answer

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?

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