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How do I save multiple user settings in runtime in C#

I am trying to make my app stay the way I left it after closing the app. Therefore I want to save set of items from ListView to the settings and I can't figure out how to do that. I've found some solutions but I believe they are outdated as they don't seem to work.
Image shows set of items in ListView which I want to save so they appear there after restarting the app:
Items
This is where I want them to appear:
Settings
And this is part of code that I've tried out so far
private void btn_SaveConfig_Click(object sender, EventArgs e)
{
int i = 0;
Settings.Default["IP"] = tBox_discoverServerFrom.Text;
Settings.Default["DiscoveredServers"] = cBox_discoveredServers.Text;
foreach (var item in lV_groups.Items)
{
var property = new System.Configuration.SettingsProperty("Group"+i);
property.PropertyType = typeof(string);
property.Name = "Group " + i;
Settings.Default.Properties.Add(property);
Settings.Default.Save();
i++;
}
}

I do not think using the Settings API is a great idea if you want to save any significant amount of data.
I would recommend the following
Create a class describing all the data you want to save. To make serialization easier it should have a parameter less constructor and public setters for all properties. This is sometimes called a Data-Transfer-Object (DTO)
Use json to serialize the object to a file. You would normally place the file in a subfolder in the local app data folder: Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData).
Do the reverse when you start the application. If there is a file, use Json to deserialize it and use it however you want.
You may optionally add logic to save the file periodically, this would allow recovery in case of application crashes. You might also want some system to keep more than one file, in case the application or computer crashes in the middle of a save operation, and the file becomes corrupt.

Storing the Users Choice in C# Winform permanently

How can I store the user's choice permanently in c# winform.
I wrote this code to fetch the setting:
string my_data_to_do = (string)Settings.Default["MyDataToDo"];
And to save the user's setting I wrote:
if (checkBox3.Checked)
{
Settings.Default["MyDataToDo"] = "Tasks In Hand";
}
else
{
Settings.Default["MyDataToDo"] = "Nothing To Do";
}
This is showing the saved data but only until I exit my application. When I exit and start my program again, all these settings gets automatically removed, and the default data comes, which I saved in Settings.settings file.
Can anyone please help me in this?

It's hard to tell if you're doing it from just the code exert you've posted, but after setting the setting like that you will need to call Settings.Default.Save() to have it persist beyond the application closing.

Count the number of times the Program has been launched

How can I get the number of times a program has previously run in c# without keeping a file and tallying. Is there a Application class or something in c# to check the count.
Please give a detailed explantion as i know nothing about it.This is A windows console application not windows forms.

You can do that my creating an Entry in the Registry. And another way is by using an Application Settings.
But I prefer Application Settings because it has less task to do.
See HERE: Creating an Application Settings.
Tutorial From Youtube

Recent versions of Windows automatically maintain this information in the registry under HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\UserAssist.
The data is obfuscated with ROT13, but that's easy to "decrypt". A free utility (with source code) is available and can serve as your starting point.

You could send a message to a database or webservice every time the program starts up (assuming there's a network connection).
You could keep a count on some form of hardware thet's not a standard storage device (therefore not technically being a file).
You could make a registry entry that you keep the count in (if you ignore the fact that the registry entry is, at some level, persisted into a file somewhere).
You could just have a file somewhere that keeps track of the count. Not sure why you're so opposed to this one in the first place....

If you are running a Winforms application, the you can easily use the Application Settings. Right click on your Solution Name --> Properties --> Settings Tab. More info and tutorial here.
Then, every time your program starts, increment this setting and save it.

Ref: Count the number of times the Program has been launched
In my knowledge Windows does not keep this information for you. You would have to tally the value somewhere (file, database, registry setting).
Better way is Application Settings as:
Create setting in app.config and then use it as:
Properties.Settings.Default.FirstUserSetting = "abc";
then, you usually do this in the Closing event handler of the main form. The following statement to Save settings method.
Properties.Settings.Default.Save();
Implementation using Registry:
static string AppRegyPath = "Software\\Cheeso\\ApplicationName";
static string rvn_Runs = "Runs";
private Microsoft.Win32.RegistryKey _appCuKey;
public Microsoft.Win32.RegistryKey AppCuKey
{
get
{
if (_appCuKey == null)
{
_appCuKey = Microsoft.Win32.Registry.CurrentUser.OpenSubKey(AppRegyPath, true);
if (_appCuKey == null)
_appCuKey = Microsoft.Win32.Registry.CurrentUser.CreateSubKey(AppRegyPath);
}
return _appCuKey;
}
set { _appCuKey = null; }
}
public int UpdateRunCount()
{
int x = (Int32)AppCuKey.GetValue(rvn_Runs, 0);
x++;
AppCuKey.SetValue(rvn_Runs, x);
return x;
}
If it's a WinForms app, you can hook the Form's OnClosing event to run UpdateCount.
Then Check tutorial to Read, write and delete from registry with C#

Can I use objects created in C# within metro ui javascript code?

I really like C# and I am familiar with it, but I also want to use HTML5/JavaScript to manage the UI for my Windows 8 Metro app. So, how can I import and use objects from a library made in C# in the Javascript files?
Example here is the starting JS code for an empty HTML5/JS project...
// For an introduction to the Blank template, see the following documentation:
// http://go.microsoft.com/fwlink/?LinkId=232509
(function () {
"use strict";
var app = WinJS.Application;
app.onactivated = function (eventObject) {
if (eventObject.detail.kind === Windows.ApplicationModel.Activation.ActivationKind.launch) {
if (eventObject.detail.previousExecutionState !== Windows.ApplicationModel.Activation.ApplicationExecutionState.terminated) {
// TODO: This application has been newly launched. Initialize
// your application here.
} else {
// TODO: This application has been reactivated from suspension.
// Restore application state here.
}
WinJS.UI.processAll();
}
};
app.oncheckpoint = function (eventObject) {
// TODO: This application is about to be suspended. Save any state
// that needs to persist across suspensions here. You might use the
// WinJS.Application.sessionState object, which is automatically
// saved and restored across suspension. If you need to complete an
// asynchronous operation before your application is suspended, call
// eventObject.setPromise().
};
app.start();
})();
Can I pull in and use libraries and objects in JS that are written in C#?
I was kind of bummed they appear to segregate C# from HTML5 based projects...

You absolutely can do this. This is the beauty of the Windows 8 and the new application model. There are a lot of places to start and look at.
Start here: http://msdn.microsoft.com/en-us/library/windows/apps/br230301(v=vs.110).aspx You can drill down further in the above link where it also links to a real basic sample. http://msdn.microsoft.com/en-us/library/windows/apps/hh779077(v=vs.110).aspx
In a nutshell, you'll create a metro class library in C# and then set the output type of your C# from a "Class Library" to a WinMD. You can then reference and use that library in your javascript project.
There is a lot of documentation on building metro apps available at http://msdn.microsoft.com/en-us/library/windows/apps

Why multiple log files are getting created with GUID using System.Diagnostics c# [duplicate]

I use TextWriterTraceListener (System.Diagnostics) in my application to trace several things like exceptions,...
The application is running on a terminal server and if there are many users using it simultaneously the listener starts to create many tracefiles with random GUIDs in the filename.
Are there possibilities or workarounds to avoid this behaviour ?

I've just taken a look at the documentation for TextWriterTraceListener and there's a note about 1/3 of the way down the page
If an attempt is made to write to a file that is in use or unavailable, the file name is automatically prefixed by a GUID
So, this would appear to be by design. If the file is indeed unavailable then there's nothing that can be done about it with the current implementation. What you could try doing is writing a custom implementation of TextWriterTraceListener that overrides the relevant Write/WriteLine methods so that the output goes to a file, per user, with a name that better suits your needs.
If what you want is for ALL logging from ALL users on the Terminal Server to go to a single file, then you'll almost certainly need to have some kind of "3rd party" process running that "owns" the file and synchronises writes to it, such as a Windows Service that is then called by your custom TextWriterTraceListener

Was the fix calling the Trace.Listeners.Add(xxx listener) multiple times on accident?
Because if you have multiple listeners added they write too all listeners when you call the Trace.writeline();
Also local IIS might be continueing to have the file in use when you shut down the application.

I am currently testing the addition of System.Diagnostics.Trace.Listeners.Clear() in my output method...
// Upon a new day re-create the TextWriterTraceListener to update our file name...
if (_date?.Day != DateTime.Now.Day) { _listener = null; }
if (_listener == null)
{
System.Diagnostics.Trace.Listeners.Clear();
_fileName = $"{DateTime.Now.ToString("yyyy-MM-dd")}_Trace.json";
// Add a writer that appends to the trace.log file:
_listener = new System.Diagnostics.TextWriterTraceListener(_fileName);
_listener.IndentSize = 4;
_listener.TraceOutputOptions = System.Diagnostics.TraceOptions.None; // TraceOptions.DateTime | TraceOptions.ThreadId;
System.Diagnostics.Trace.AutoFlush = true;
System.Diagnostics.Trace.Listeners.Add(_listener);
// Obtain the Console's output stream, then add that as a listener...
System.Diagnostics.Trace.Listeners.Add(new System.Diagnostics.TextWriterTraceListener(Console.Out));
}