Are admins able to restrict usage of %AppData%? - windows

Currently i have a VSTO Outlook addin that is using the default settings provider to manage configurations. All User configs are marked at Local scope and are thus saved under %LocalAppData%.
I have a reason to change them to be Roaming (%AppData%) scope and it seems to work on my computer (local profile), but there is some uncertainty that it might not be that way for everyone.
So my concern is, is there any scenario in AD/GP environments or otherwise, if i did swap over from Local to Roaming where the addin would cease to work due to the Roaming folder being inaccessible or something like that?
Been trying to figure out any scenarios like this but really the only things i can find is that:
administrators may turn off roaming profiles, which would just make the roaming folder act like the local folder? (addin still works locally),
admins may limit the size of the profile which breaks syncing. (addin still works locally)
admins may exclude my folder from syncing (addin still works locally)
Basically worst case scenario i've been able to come up with is that configs will be local to the device, which is exactly how it works now, no problem.
For those that do use roaming profiles, if i cause them exceed their quota would that possibly break the whole profile?
What else could possibly go wrong? Which pitfalls am i missing (and what are the best practices to overcome them (c# bonus))?

The definition for the Roaming folder purpose according to Microsoft is
Windows uses the Roaming folder for application specific data, such as
custom dictionaries, which are machine independent and should roam
with the user profile.
According to this, you may and should use the roaming folder for application data. That data may be roaming with the user profile, but it won't be removed (and definitely won't lose accessibility) at any time. (unless the user erased it or limited it)
more detailed source
You may notice in the source link that the Roaming folder is in comparison with "Documents And Settings" of good old Windows XP. definitely a place to store application data with safety...

Related

Shared dev machine and local workspaces

Suppose we have a machine shared by many developers. Developers have access to different parts of the project, they don't see all the same complete source code. Suppose also that we use this shared machine even to test job interviewer on some test programs.
How do we protect source code in the local workspaces? I mean, we wouldn't want that developers/job interviewer are able to see/copy what they are not allowed to. We use Visual Studio & TFS 2012 in a Windows environment.
Thanks.
If your users do not have admin permissions, you could store the workspace in the users profile. So it is only accessible for them (and administrators). But you should be careful with this, because the size of the profile could grow extremely, which would have effect to your login time on other machines. Also some companies set a max size for profiles, which could be exceeded fast using this method.
Another option would be to store the workspace on a network share, which has personalized permissions.

Mercurial remotes on the file system instead of http server

I'm currently working on a migration from svn to mercurial. My needs are plain and simple, I need source control over an intranet in our company. I see examples everywhere for setupping remote repos over IIS. I just don't see the point when I can just make a share on a server.
Can I still setup authorizations and authentications on repos using NTFS permissions?
Am I missing something?
Thank you
Putting a repository on a file share works, but it's not the way recommended by the Mercurial team.
See the "shared disk" part of Publishing Repositories on the HG wiki:
generally restricted to intranets, not generally recommended due to general issues with network filesystem reliability
Be sure to check out Chris Becke's answer as well, because he points out another valid disadvantage (people with write access deleting stuff from the network share, be it intentionally or not).
If you are aware of (and can live with) these things, putting the repositories on the network share is without a doubt the easiest way to setup.
My personal experience is that it works perfectly as long as the Windows share is on a "real" Windows machine.
At work we're using a share on a real Windows server without problems, but at home I ran into issues with a NAS (which behaves like a Windows share but actually runs on Linux).
You can read more about my experiences here:
Can you 'push' to network share using Mercurial on 64bit Windows 7?
There are a number of reasons to prefer, well, anything at all to a writable file share.
In essence it comes down to, there is a limited amount of damage someone can do with the ability to do a push via a web-method.
A read/write share on the other hand is necessary to do a push, but also allows a user to delete an entire repo, history and all.
Without even invoking malicious intent, people (or rogue software agents) have been know to navigate to random network shares and accidentally drag a file to someplace it doesn't belong.
The best reason to lock your PC is not because your co-workers find it amusing to use an unlocked email account to send porn to HR, but because its amazing what a cleaning lady can do with a rag and a keyboard. Its also amazing what Music Library applications can find while scanning all shares in a workgroup, and carefully "move" and catalog to someones Library.

Does Windows 7 restrict folder access as Vista does?

I noticed that in my application, most compatibility problems were caused by 'access denied' for some folders, such as:
Application Data [C:\ProgramData]
Desktop [C:\Users\Public\Desktop]
Documents [C:\Users\Public\Documents]
Favorites [C:\Users\Public\Favorites]
Start Menu [C:\ProgramData\Microsoft\Windows\Start Menu]
Templates [C:\ProgramData\Microsoft\Windows\Templates]
Does Windows 7 have the same problem as Vista?
With help from the members of Stack Overflow, I know that on Vista I can use CSIDL_APPDATA to enable the file access without UAC problems or 'access denied' errors.
Is this also valid for Windows 7?
It's not a "problem", it's a feature. It's called User Account Control (UAC), and it's one of the ways that system security was tightened under Windows Vista. Windows 7 indeed retains a similar security model.
There's absolutely no reason that your application should need to mess with system folders in the first place. As you've already learned, Windows provides a number of locations for applications to store data, both temporarily and permanently. Microsoft has been recommending for a long time that you take advantage of these folders: they were the preferred location for storing data even under previous versions of Windows. The fact that you ignored this advice, yet your application continued to work, was actually the bug. The fact that later versions of Windows finally closed that security vulnerability, thus breaking your application, should be neither unexpected nor unappreciated.
You can find more information about where to store your data on this page. Also see this blog article, which attempts to summarize the array of technical documentation into a handy table. And as always, Raymond Chen provides a simple, yet instructive, overview of the differences between the locations:
The most important difference between My Documents and Application Data is that My Documents is where users store their files, whereas Application Data is where programs store their files.
In other words, if you put something in CSIDL_MYDOCUMENTS (My Documents), you should expect the user to be renaming it, moving it, deleting it, emailing it to their friends, all the sorts of things users do with their files. Therefore, files that go there should be things that users will recognize as "their stuff". Documents they've created, music they've downloaded, that sort of thing.
On the other hand, if you put something in CSIDL_APPDATA (Application Data), the user is less likely to be messing with it. This is where you put your program's supporting data that isn't really something you want the user messing with, but which should still be associated with the user. High score tables, program settings, customizations, spell check exceptions...
There is another directory called CSIDL_LOCAL_APPDATA (Local Settings\Application Data) which acts like CSIDL_APPDATA, except that it does not get copied if the user profile roams. (The "Local Settings" branch is not copied as part of the roaming user profile.) Think of it as a per-user-per-machine storage location. Caches and similar non-essential data should be kept here, especially if they are large. Other examples of non-roaming per-user data are your %TEMP% and Temporary Internet Files directories.

Suggested file location that will be editable by all windows users?

I'm building a product that involves
a windows service caching data on the local machine,
user processes reading that data and writing their own data,
the service in turn writing back that data to a server.
Where should I put the data files for this, such that they'll be shared by all users and read/writable? The software will operate in a corporate environment where desktops are sometimes pretty locked-down, so for instance some users won't have write rights to C:\Program Files.
I don't think C:\Documents And Settings\All Users\Application Data\ is a good candidate - I think by default only Admins & Power Users have write access here.
I could use each user's Application Data folder, but this would be a bit of a pain as different people could use each machine ... so it'd be simpler if there was just one shared location.
I'm developing in C# .net 2005, but that's probably not too relevant.
Unfortunately you have no real choice. You must (you really must) call SHGetSpecialFolderLocation to get the path to c:\users\public\AppData (which is the name of the folder you linked above, but on Vista and possibly Windows 7)
Then you MUST create your own app folder therein. And then, you MUST, use the security APIs to modify the ACL of the created folder.
There is NO folder on the system with a default ACL that allows multiple non administrator users to read AND write the same files.
c:\users\public\AppData is the closest. Modifying the ACL of a application folder here seems the best approach. Of course, once one has resorted to ACL modification, the folder really could be created anywhere at all. But that could surprise system administrators and result in weired security holes.

When - and why - should you store data in the Windows Registry?

As a developer, tools that store configuration/options in the registry are the bane of my life. I can't easily track changes to those options, can't easily port them from machine to machine, and it all makes me really yearn for the good old days of .INI files...
When writing my own applications, what - if anything - should I choose to put in the registry rather than in old-fashioned configuration files, and why?
Originally (WIN3) configuration was stored in the WIN.INI file in the windows directory.
Problem: WIN.INI grew too big.
Solution (Win31): individual INI files in the same directory as the program.
Problem: That program may be installed on a network and shared by many people.
Solution(Win311): individual INI files in the user's Window directory.
Problem: Many people may share a windows folder, and it should be read-only anyway.
Solution (Win95): Registry with separate sections for each user.
Problem: Registry grew too big.
Solution (WinXP): Large blocks of individual data moved to user's own Application Data folder.
Problem: Good for large amounts of data, but rather complex for small amounts.
Solution (.NET): small amounts of fixed, read-only data stored in .config (Xml) files in same folder as application, with API to read it. (Read/write or user specific data stays in registry)
Coming at this both from a user perspective and a programmers perspective I would have to say there really isn't a good exceuse to put something in the registry unless it is something like file associations, or machine specific settings.
I come from the school of thought that says that a program should be runnable from wherever it is installed, that the installation should be completely movable within a machine, or even to another machine and not affect the running of it.
Any configurable options, or required dlls etc, if they are not shared should reside in a subdirectory of the installation directory, so that the whole installation is easily moved.
I use a lot of smaller utility like programs, so if it cant be installed on a usb stick and plugged into another machine and just run, then its not for me.
When - You are forced to due to legacy integration or because your customer's sysadmin says "it shall be so" or because you're developing in an older language that makes it more difficult to use XML.
Why - Primarily because the registry is not as portable as copying a config file that is sitting next to the application (and is called almost the same).
If you're using .Net2+ you've got App.Config and User.Config files and you don't need to register DLL's in the registry so stay away from it.
Config files have their own issues (see below), but these can be coded around and you can alter your architecture.
Problem: Applications needed configurable settings.
Solution: Store settings in a file (WIN.INI) in the Windows folder - use section headings to group data (Win3.0).
Problem: WIN.INI file grew too big (and got messy).
Solution: Store settings in INI files in the same folder as the application (Win3.1).
Problem: Need user-specific settings.
Solution: Store user-settings in user-specific INI files in the user's Window directory (Win3.11) or user-specific sections in the application INI file.
Problem: Security - some application settings need to be read-only.
Solution: Registry with security as well as user-specific and machine-wide sections (Win95).
Problem: Registry grew too big.
Solution: User-specific registry moved to user.dat in the user's own "Application Data" folder and only loaded at login (WinNT).
Problem: In large corporate environments you log onto multiple machines and have to set EACH ONE up.
Solution: Differentiate between local (Local Settings) and roaming (Application Data) profiles (WinXP).
Problem: Cannot xcopy deploy or move applications like the rest of .Net.
Solution: APP.CONFIG XML file in same folder as application - , easy to read, easy to manipluate, easy to move, can track if changed (.Net1).
Problem: Still need to store user-specific data in a similar (i.e. xcopy deploy) manner.
Solution: USER.CONFIG XML file in user's local or roaming folder and strongly-typed (.Net2).
Problem: CONFIG files are case-sensitive (not intuitive to humans), require very specific open/close "tags", connection strings cannot be set at run-time, setup projects cannot write settings (as easily as registry), cannot easily determine user.config file and user settings are blown with each new revision installed.
Solution: Use the ITEM member to set connection strings at runtime, write code in an Installer class to change the App.Config during install and use the application settings as defaults if a user setting is not found.
Microsoft policy:
Before windows 95, we used ini files for application data.
In the windows 95 - XP era, we used the registry.
From windows Vista, we use ini files although they are now xml based.
The registry is machine dependent. I have never liked it because its getting to slow and it is almost imposible to find the thing you need. That's why I like simple ini or other setting files. You know where they are (application folder or a user folder) so they are easy portable, and human readable.
Is the world going to end if you store a few window positions and a list of most recently used items in the Windows registry? It's worked okay for me so far.
HKEY-CURRENT-USER is a great place to store trivial user data in small quantities. That's what it's for. It seems silly not to use for its intended purpose just because others have abused it.
Registry reads and writes are threadsafe but files are not. So it depends on whether or not your program is single threaded.
Settings that you want to have available in a user's roaming profile should probably go in the registry, unless you actually want to go to the effort of looking for the user's Application Data folder by hand. :-)
If you are developing a new app and you care about portability you should NEVER store data in windows registry since other OS don't have a (windows) registry (duh note - this may be obvious but gets often overlooked).
If you're only developing for Win platforms ... try to avoid it as much as possible. Config files (possibly encrypted) are a way better solution. There's no gain in storing data into the registry - (isolated storage is a much better solution for example if you're using .NET).
Slightly off-topic, but since I see people concerned about portability, the best approach I've ever used is Qt's QSettings class. It abstracts the storage of the settings (registry on Windows, XML preference file on Mac OS and Ini files on Unix). As a client of the class, I don't have to spend a brain cycle wondering about the registry or anything else, it Just Works (tm).
http://doc.trolltech.com/4.4/qsettings.html#details
Personally I have used the registry to store install paths for use by the (un)install scripts. I'm not sure if this is the only possible option, but seemed like a sensible solution. This was for an app that was solely in use on Windows of course.
Usually, if you don't put settings in registry, you use it mostly to get current Windows settings, change file associations, etc.
Now, if you need to detect if your software is already installed, you can make a minimal entry in registry, that's a location you can find back in any config. Or search a folder of given name in Application Data.
If I look at my Document and Settings folder, I see lot of softwares using the Unix dot notation for setting folders:
.p4qt
.sqlworkbench
.squirrel-sql
.SunDownloadManager
.xngr
.antexplorer
.assistant
.CodeBlocks
.dbvis
.gimp-2.4
.jdictionary
.jindent
.jogl_ext (etc.)
and in Application Data, various folders with editor names or software names. Looks like being the current trend, at least among portable applications...
WinMerge uses a slightly different approach, storing data in registry, but offering Import and Export of options in the config dialog.
I believe that Windows Registry was a good idea, but because of great abuse from application developers and standard policies not encouraged/mandated by Microsoft grew into an unmanageable beast. I hate using it for the reasons you've mentioned, there are however some occasions that it makes sense using it:
Leaving a trace of your application after your application has been uninstalled (e.g. remember user's preferences in case the application is installed again)
Share configuration settings between different applications - components
In .NET there really is NOT ever a need.
Here are 2 examples that show how to use Project proerties to do the this.
These examples do this by Windows User Project Properties, but the same could/can be done by Application as well.
More here:
http://code.msdn.microsoft.com/TheNotifyIconExample
http://code.msdn.microsoft.com/SEHE
(late to the discussion but) Short Answer: Group Policy.
If your customer's IT department wants to enforce settings related to Windows or the component(s) you're writing or bundling in, such as a link speed, or a custom error message, or a database server to connect to, this is still typically done via Group Policy, which makes its ultimate manifestation as settings stored in the registry. Such policies are enforced from the time Windows starts up or the user logs in.
There are tools to create custom ADMX templates that can map your components' settings to registry locations, and give the administrator a common interface to enforce policies (s)he needs to enforce while showing them only those settings that are meaningful to enforce this way.

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