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System.UnauthorizedAccessException when writing to the install path

I'm trying to download multiple files from an SFTP server and save them to the install path (or actually, ANY path at the moment just to get it working). However, I get an UnauthorizedAccess Exception no matter where I try to save the files.
As far as was aware, there are no special permissions required to save files to the install dir (Hence why I chose this folder).
Thread myThread = new Thread(delegate() {
string host;
string username;
string password;
// Path to folder on SFTP server
string pathRemoteDirectory = "public_html/uploads/17015/";
// Path where the file should be saved once downloaded (locally)
StorageFolder localFolder = Windows.ApplicationModel.Package.Current.InstalledLocation;
string pathLocalDirectory = localFolder.Path.ToString();
var methods = new List<AuthenticationMethod>();
methods.Add(new PasswordAuthenticationMethod(username, password));
//TODO - Add SSH Key auth
var con = new ConnectionInfo(host, 233, username, methods.ToArray());
using (SftpClient sftp = new SftpClient(con))
{
try
{
sftp.Connect();
var files = sftp.ListDirectory(pathRemoteDirectory);
// Iterate over them
foreach (SftpFile file in files)
{
Console.WriteLine("Downloading {0}", file.FullName);
using (Stream fileStream = File.OpenWrite(Path.Combine(pathLocalDirectory, file.Name)))
{
sftp.DownloadFile(file.FullName, fileStream);
Debug.WriteLine(fileStream);
}
}
sftp.Disconnect();
}
catch (Exception er)
{
Console.WriteLine("An exception has been caught " + er.ToString());
}
}
});
Connection to the server is all fine, the exception occurs on this line.
using (Stream fileStream = File.OpenWrite(Path.Combine(pathLocalDirectory, file.Name)))
I'm must be missing something obvious here but it's worth noting that I've also tried writing to Special Folders like the Desktop, the users Document folder and also direct to the C:/ drive, all with the same exception. I'm also running with Administrator privileges and I have the correct permissions set in the folders.

It turns out that SFTP was counting '.' and '..' as files and trying to download those, when obviously '.' is the set SFTP folder and '..' is the previous folder. This was causing a permissions exception, not 100% sure why. Simply iterating over the files to make sure they're not named '.' or '..' fixed the issue. Code below.
sftp.Connect();
var files = sftp.ListDirectory(pathRemoteDirectory);
// Iterate over them
foreach (SftpFile file in files)
{
if (!file.IsDirectory && !file.IsSymbolicLink)
{
using (Stream fileStream = File.OpenWrite(Path.Combine(pathLocalDirectory, file.Name)))
{
sftp.DownloadFile(file.FullName, fileStream);
Debug.WriteLine(pathLocalDirectory);
}
}
else if (file.Name != "." && file.Name != "..")
{
Debug.WriteLine("Directory Ignored {0}", file.FullName);
}
else if (file.IsSymbolicLink)
{
Debug.WriteLine("Symbolic link ignored: {0}", file.FullName);
}
}
sftp.Disconnect();

You have multiple problems here. The parent folder ("..") reference you answered is one blocker, but that doesn't address the deeper problem that the InstalledLocation is read-only.
UWP apps do not have direct access to most file system locations. By default they can read and write to their ApplicationData directory and they can read from (but not write to) the InstalledLocation. The failures you saw for Desktop, Documents, and C:\ are all expected.
Other locations (including Desktop, Documents, and C:) may be granted access by the user either explicitly or via the app's declared capabilities. They can be accessed via the file broker through the StorageFile object.
See the UWP File access permissions documentation:
The app's install directory is a read-only location. You can't gain
access to the install directory through the file picker.
For the long term you'll want to download your files somewhere else: probably into one of the ApplicationData folders. These folders are the only ones with no special permission requirements for UWP apps.
So why does this work for you now?
You're running into a debugging quirk where your app is not fully installed but is staged from your VS project directory. This allows the app to write to the staged install directory, but once it is properly deployed into Program Files\WindowsApps writing to the InstalledLocation will fail.

Try Path.GetTempPath();. You should have permission there.
When it says you don't have permission, you don't. 8-)
Also, there's no such thing as "no special permissions". Everything requires some level of permission for access.

UWP C# Windows IoT Read Text Line to Process Word [duplicate]

I am trying to read a text file named thedata.txt that has a list of words that I want to use in a hangman game. I have tried different ways, but I can't figure out where the file gets placed, if at all when the app runs. I added the file to my project, and I have tried setting the build properties to content, and then embedded resource, but can't find the file. I have made a Windows 10 universal app project. The code I tried looks like this:
Stream stream = this.GetType().GetTypeInfo().Assembly.GetManifestResourceStream("thedata.txt");
using (StreamReader inputStream = new StreamReader(stream))
{
while (inputStream.Peek() >= 0)
{
Debug.WriteLine("the line is ", inputStream.ReadLine());
}
}
I get exceptions.
I also tried to list the files in another directory:
string path = Windows.Storage.ApplicationData.Current.LocalFolder.Path;
Debug.WriteLine("The path is " + path);
IReadOnlyCollection<StorageFile> files = await Windows.Storage.ApplicationData.Current.LocalFolder.GetFilesAsync();
foreach (StorageFile file2 in files)
{
Debug.WriteLine("Name 2 is " + file2.Name + ", " + file2.DateCreated);
}
I don't see the file there either...I want to avoid hard coding the list of names in my program. I'm not sure what the path that the file is placed.

the code is very simple, you just have to use a valid scheme URI (ms-appx in your case) and transform your WinRT InputStream as a classic .NET stream :
var file = await StorageFile.GetFileFromApplicationUriAsync(new Uri("ms-appx:///thedata.txt"));
using (var inputStream = await file.OpenReadAsync())
using (var classicStream = inputStream.AsStreamForRead())
using (var streamReader = new StreamReader(classicStream))
{
while (streamReader.Peek() >= 0)
{
Debug.WriteLine(string.Format("the line is {0}", streamReader.ReadLine()));
}
}
For the properties of the embedded file, "Build Action" must be set to "Content" and "Copy to Ouput Directory" should be set to "Do not Copy".

You can't use classic .NET IO methods in Windows Runtime apps, the proper way to read a text file in UWP is:
var file = await ApplicationData.Current.LocalFolder.GetFileAsync("data.txt");
var lines = await FileIO.ReadLinesAsync(file);
Also, you don't need a physical path of a folder - from msdn :
Don't rely on this property to access a folder, because a file system
path is not available for some folders. For example, in the following
cases, the folder may not have a file system path, or the file system
path may not be available. •The folder represents a container for a
group of files (for example, the return value from some overloads of
the GetFoldersAsync method) instead of an actual folder in the file
system. •The folder is backed by a URI. •The folder was picked by
using a file picker.

Please refer File access permissions for more details.
And Create, write, and read a file provides examples related with File IO for UWP apps on Windows 10.
You can retrieve a file directly from your app's local folder by using an app URI, like this:
using Windows.Storage;
StorageFile file = await StorageFile.GetFileFromApplicationUriAsync("ms-appdata:///local/file.txt");

Creating Files and Folders in UWP

Ive looked at at so many stackoverflow posts and articles but still didnt manage to create a file in UWP. In WPF it was really easy but UWP works differently.
I added the following in my manifest file:
<Capabilities>
<uap:Capability Name="documentsLibrary" />
</Capabilities>
Now im not sure what to do next. Inside my documents folder I have a subfolder named "Project Files". I want to create folders and files in there. How is this done in UWP? I really dont understand.

As microsoft states in their docs, its recommenced not to use the documents Library through an UWP app, instead opt for the built in storage unless its absolutely necessary.
There is an easy way to get around that if you use a folder picker
private async void buttonClick(){
FolderPicker folderPicker = new FolderPicker();
folderPicker.SuggestedStartLocation = PickerLocationId.DocumentsLibrary;
folderPicker.FileTypeFilter.Add("*");
StorageFolder folder= await folderPicker.PickSingleFolderAsync();
if (folder != null) {
// do Things On Folder
}
else
{
MessageDialog dialog = new MessageDialog("you selected nothing");
await dialog.ShowAsync();
}
}
The above opens up a folder select dialog, it returns the folder the user picked, its the recommended way for accessing locations outside your app's folder.
Here is how to Create a new file in this folder:
string name ="myTitle.txt";
await folder.CreateFileAsync(name, CreationCollisionOption.GenerateUniqueName);
here is how to open and write a file:
try {
StorageFile myFile = await folder.GetFileAsync(name);
await Windows.Storage.FileIO.WriteTextAsync(myFile, "myStringContent");
}
catch (Exception e)
{
Debug.WriteLine("Failure: "+e.Message);
return;
}
remember you can always avoid opening up a dialog if you use the local storage instead, it returns you app's storage folder in one line, like this:
var folder= ApplicationData.Current.LocalFolder;

I believe in UWP using the documents library is neither recommended or permitted. See https://blogs.msdn.microsoft.com/wsdevsol/2013/05/09/dealing-with-documents-how-not-to-use-the-documentslibrary-capability-in-windows-store-apps/
If you side load the app and use the documents library capability the app gets access only to declared file types, not to everything in documents.
See https://msdn.microsoft.com/en-us/library/windows/apps/hh464936.aspx#special_capabilities
Note that this special capability will not let you pass through app certification in Store, unless you go through some special procedure contacting MS first.
To create folder, use StorageFolder. To create file, use StorageFile.
See https://learn.microsoft.com/en-us/windows/uwp/files/quickstart-reading-and-writing-files

Windows 10 UWP App XElement.Save() "Access is denied" exception

I'm writing a Windows 10 UWP App, and I'm hitting a snag. I have a Settings.xml in the root of the app folder that I will use to store the DB connection information, as well as a few ancillary settings. I can load the XML fine, and my function to edit works (I can extract the XML through debug and see the changes). My problem comes when trying to write the edited file. I understand that I don't have direct access to the file system with UWP, however I've tried several different methods I've found online to work within my constraints and still can't find one that works. I always come back with an "Access is denied" error in some form or another. Here is a snippet of what my Save function looks like right now. Any help would be greatly appreciated.
try
{
XElement xmlSettings = XElement.Load(uri: "Settings.xml");
XElement xmlNode;
//Do Stuff (clipped for brevity).
StorageFolder folder = ApplicationData.Current.LocalFolder;
StorageFile file = await folder.CreateFileAsync(desiredName: "Settings.xml", options: CreationCollisionOption.ReplaceExisting);
Stream stream = await file.OpenStreamForWriteAsync();
xmlSettings.Save(stream);
Error = "";
}
catch (Exception e)
{
Error = "SaveSettings";
}

I added an xml file to my solution (in the root) and copy pasted your code.
It runs the first time, but gets the exception the second time. The reason is that your stream is not closed. You should use it with using:
using (Stream stream = await file.OpenStreamForWriteAsync())
{
xmlSettings.Save(stream);
}
With this change the code worked even the second time.

Access to path denied but the file has no restrictions

I'm new to C# and not an expert at programming in general, but I can't seem to figure out what is causing this problem. I am letting the user pick a XML file and then I want to read it's contents. This is in C# making a universal windows 10 app
This is the error I'm getting:
An exception of type 'System.UnauthorizedAccessException' occurred in
mscorlib.ni.dll but was not handled in user code
Additional information: Access to the path 'C:\temp\file.xml' is
denied.
public async static void pickFile()
{
FileOpenPicker openPicker = new FileOpenPicker();
openPicker.ViewMode = PickerViewMode.List;
openPicker.SuggestedStartLocation = PickerLocationId.DocumentsLibrary;
openPicker.FileTypeFilter.Add(".xml");
StorageFile file = await openPicker.PickSingleFileAsync();
if (file != null)
{
var t = Task.Run(() => { reset(file.Path); });
}
}
then
private static void reset(string path)
{
String LocationDatafilename = path;
XmlReaderSettings settings = new XmlReaderSettings();
XmlReader reader = XmlReader.Create(LocationDatafilename, settings);
XmlDocument LocationDataXml = new XmlDocument();
LocationDataXml.Load(Globals.reader);
}
When I get to XmlReader.Create that's when I'm getting the error. When I look for the cause, the only thing I find is due to permissions, but that isn't the case. Any help would be appreciated. Thanks.

You need to operate on the StorageFile directly, since your app doesn't have permissions to directly read the user's files. You can either use the WinRT XML API or you can keep using the .NET API and use the stream-based Create function instead of the one that takes a file name.

Run sysinternal's ProcMon app, and at the same time run your application. Find the file in the procmon capture, and in the CreateFile entry, you'll find the creation Disposition. This will give you a clue why the creation failed. Also, select the "User" column to show the user performing the operation.

While Peter Torr's answer is correct and is the way Microsoft wants these things to be done, it is possible to make (at least parts of) the OP's code work as well. The reset method will work, if the path is to one of the directories you have permission for. To get these you can use ApplicationData.Current. This object contains properties like LocalFolder, LocalCacheFolder or (what could be interesting for your use case) SharedFolder.