What is the purpose of program files directory in windows? - windows

I wonder about this because we are developing an application, after installation some files were copied to program files and some to user profile directory. But, we found some issues w.r.t program files. Now all files are installed in the current user's directory. Even Google Chrome, does so. What do you think?

If you install a given application on 10 different accounts, do you really want the application to exist 10 times on disk?

The program files directory is for just that, the executable files, dlls, assemblies and other executable code and non editable configuration data associated with a program. The user profile directory is for data and code associated with the individual user.

The program files directory in Windows is a place where all the installed files go.
But there are some customizations needed depending on users. Those go into user's directory.
Like Downloads folder, customization of Mozilla firefox, Winamp, etc.
There has to be different profiles for each user to customize the applications.
But the commonly needed files of a software need not be installed in each user account; hence they are installed in Program Files

Since Vista the Program Files directory has been marked as off limits so applications can't write to it by default unless given admin privileges.
This is for better security to stop other applications manipulating existing installed applications.
There is a good write up of this here on how to work with UAC but also learning to write more secure applications.
http://msdn.microsoft.com/en-au/magazine/cc163486.aspx

Related

visual studio setup project - install for all users

I have a visual studio setup project which installs my files to the program files folder and also writes some stuff into the registry and in addition some of the files are com visible (so there is more confusing stuff written to the registry).
Therefore I have to install it as an administrator - this works fine. And this administrator and every other administrator is able to start the program. But using a standard user I am not able to start the program.
All registry entries are there for the standard user - and it also has enough rights to access the file in the Program Files folder.
Could there be a problem with the ComVisibility? (Which is needed because it's actually a DLL working as a plugin for Solidworks)
You just need to look at the code in your app and see what it does that limited users can't do. Installing it for all users does not mean that it automatically allows limited users to violate security. Just find out what it's doing when it gets the security error (which is what you believe it is).
Limited users have never been able to write to restricted areas such as the ProgramFiles folder, CommonFiles folder, HKLM etc. That's a common reason for limited user issues with apps.

How to prevent file redirection to VirtualStore for read/write files?

I am using C# with .net 2.0
I am saving my program data in a file under: C:\ProgramData\MyProgramName\fileName.xml
After installing and running my application one time I uninstalled it (during uninstallation I'm removing all the files from "program data") and then I reinstall the application, and ran it.
The strange thing is that my application started as if the files in program data existed - means, I had old data in my app even though the data file was deleted.
When running:
File.Exists("C:\ProgramData\MyProgramName\fileName.xml")
I got "true" even though I knew for sure that the file does not exist.
The thing became stranger when I ran the application as admin and then the file didn't exist.
After a research, I found out that when running my application with no admin privileges instead of getting:
C:\ProgramData\MyProgramName\fileName.xml
I get
C:\Users\userName\AppData\Local\VirtualStore\ProgramData\MyProgramName\fileName.xml
and indeed there was a file that existed from the previous installation (that I obviously didn't delete, because I didn't know it existed).
So just guide me how could I stop this when apps running with no admin right.
I do not want to create any file automatically in VirtualStore folder. Please discuss all the possible ways to stop this.
First, ask yourself, do this need to be globally saved for all users?
If it doesn't have to be, save the file in Application Data instead, you can get the path with Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), it should always reliably expand to C:\Users\Username\AppData\Roaming\. Do note that this path is unique for each user though.
If you have to, you're out of luck. There is no reliable way to store application data for all users without admin rights (or UAC) on any Windows post-XP that's not extremely hacky, like storing your data in the Public user (which may or may not be possible, I can't check right now).
An approach to solving this is to use the Environment.SpecialFolder.CommonApplicationData location, but with some very important caveats & setup.
CommonApplicationData is
The directory that serves as a common repository for
application-specific data that is used by all users.
This location is described further here and here.
Important requirements and restrictions are given in another SO answer: https://stackoverflow.com/a/22107884/3195477
which said in part:
The recommended solution is for your installer to create a sub
directory of C:\ProgramData for your shared storage. And that sub
directory must be given a permissive ACL by the installation program.
That is what grants the desired access to all standard users.
Otherwise the program running with standard user permission will still not be all equally able to read/write files in that location for all users.
I found a work around for this issue when transferring a very old win32 app to windows 7 & 10. The program wrote to a database on C:\Program Files... but the OS auto changed the path to virtual store. However the database was required globally. By changing compatablilty mode to Windows 95 or XP SP2 and always running as administrator the database was worked on directly in C:\Program Files\etc.
There are security implications for this and the box was removed from all networks and adapters disabled etc.

Where should executable files be installed to in Windows 7?

I'm currently working on my applications installer and I'm wondering where the executable files should be installed to in Windows 7.
If I'm installing as admin my executables files get put in C:\Program Files.
If I install my product as a normal user where should the executables be put?
Thanks in advance.
Which installer are you using?
MSI runs in elevated privileges. You can install your application in program files folder
Put the files in the user folder.
This will mean that the application is only available to that user.
You should probably store that in the AppData directry, as I saw you mention in reply to #ChrisF. Remember that the user can move this directory though, so I wouldn't point to it explicitly. There is an environment variable that you can grab, that only applies to the logged-in user, which is %AppData%.
Keep in mind that putting it in %AppData%/Roaming would follow the user across multiple machines on the same Domain and %AppData%/Local would just stay on the one machine.
The executables should be under Program Files, who's precise location may vary from installation to installation. This means that the setup should run elevated. If InnoSetup makes .msi files, they will request elevation. If it makes a file called setup.exe, it will also request elevation. If for some reason the exe has a different name, like GetStarted.exe, then you should hand create an external manifest (GetStarted.exe.manifest) and put in requireAdministrator for the requestedExecutionLevel which will ensure your installer requests elevation.
Regardless of how it requests elevation, if the user doing the install is an admin (eg you) they will just have to click consent. If they are not an admin they will need to get an admin to consent for them. After that the installer will be able to write to Program Files.
If it's important to you that non admins be able to install the app then have the executables go under the users profile - but that would not be my first choice. The protection given to Program Files means that users are less likely to find themselves with messed up copies of your application if you install it to the protected area.

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

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. :-)
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?
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.
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
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.
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 :)
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.

How to pass security issues in Vista?

I have a vb6 application. I am unable to carry out the following on a Windows Vista machine:
Register a .DLL from the Users directory
Start another .EXE
Write to a file in the Users directory.
How can I overcome these issues?
This is by design. Software is supposed to require admin rights for installation (including update/upgrades). You got away with it in XP because so many people ran as administrator. If you're registering a dll after installation, you're doing something wrong.
You should be able to do this without issue, but only with the same rights as the user that the current app is running under. What is this exe trying to do, and would a standard user normally have those permissions?
What specific folder in the user's directory? Again: a user should have write access to most of the their own profile, but not necessarily as much outside of that as you think.
You have access to write to the c:\users\ directory. Going to another users directory is a bit of a security problem that you're not going to work around.
As far as registering an assembly from a users directory... There is a directory under c:\users\\AppData\Local\assembly which you should have access to for temporary assemblies
Starting another exe is trivial... As long as it's installed in the normal \program files.. path.
It really sounds like maybe you need to reevaluate how your application works.
Some suggestions:
Move to Reg-Free COM where it can handle things (i.e. not for ActiveX EXEs, DCOM).
We'd need more information. This should be no problem unless there are permissions issues.
Users are not supposed to be creating files outside of their own profiles, CommonAppData, and application-defined locations (often on non-system drives). More information is required to give any really useful answer.

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