We Keep Coding

c# win10 error trying to read/update registry

I am trying to access Software\Microsoft\Windows\CurrentVersion\Group Policy Objects{AEE4EB78-4042-42EC-9C84-D08BA6C3047B}Machine\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate to read update value PauseFeatureUpdatesStartTime.
Trying to access entire path was failing, so I started trying it iece by piece.
key = Registry.CurrentUser.OpenSubKey(#"Software\Microsoft\Windows\CurrentVersion"); worked fine but
key = Registry.CurrentUser.OpenSubKey(#"Software\Microsoft\Windows\CurrentVersion\Group Policy Objects"); fails with key equal to NULL?!?
I believe the key path is correct because I am displaying it in regedit and
regedit is displaying "Computer\HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Group Policy Objects{AEE4EB78-4042-42EC-9C84-D08BA6C3047B}Machine\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate" as the path.
NOTE!!! these keys\values may not exist if you have not "activated" then with gpedit.msc. In gpedit, look for "Computer Configuration\Administrative Templates\Windows Components\Windows Update\Windows Update For Business". You have to "activate" the first two items.
Any thoughts?
thanks,

Running .bat file whenever a user is logged in

I want a .bat file to run whenever the machine starts (or alternatively whenever a user is signed in)
For this I've made this piece of code:
string subKey = "SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run";
RegistryKey key;
if (ClientSystem.Is64BitOperatingSystem)
{
key = RegistryKey.OpenBaseKey(
RegistryHive.LocalMachine,
RegistryView.Registry64
).OpenSubKey(subKey);
}
else
{
key = Registry.LocalMachine.OpenSubKey(subKey, true);
}
key.SetValue("websocket", #"c:\websocket\run.bat"); // error here
when running this I get an error telling me that I don't have permission change the file.
As #Tolanj mentions it might be an idea to add the actual error message:
Der kan ikke skrives til registreringsdatabasenøglen.
Which would translate to something like
Couldn't write to the database registration key
The user running the program has adminstrator rights and the program is run as administrator
How would I go around changing the permission in order to allow the script to be run when the machine starts or is there a better way to achieve the functionality I'm looking for?

key = RegistryKey.OpenBaseKey(
RegistryHive.LocalMachine,
RegistryView.Registry64
).OpenSubKey(subKey);
needs to be:
key = RegistryKey.OpenBaseKey(
RegistryHive.LocalMachine,
RegistryView.Registry64
).OpenSubKey(subKey, true);
to open for modify

Modify an existing registry key value in c#

I want to modify a data in registry path SOFTWARE\Wow6432Node\Program\SubProgram using C# code in windows 7. I am able to read the value but I can't write into Registry.
Here is the code:
RegistryKey SUBKEY;
RegistryKey TAWKAY = RegistryKey.OpenRemoteBaseKey(Microsoft.Win32.RegistryHive.LocalMachine, "");
string subkey = "SOFTWARE\\Wow6432Node\\Program\\SubProgram ";
if (TAWKAY.OpenSubKey(subkey) != null) // Get values from Registry
{
TAWKAY = RegistryKey.OpenRemoteBaseKey(Microsoft.Win32.RegistryHive.LocalMachine, "");
SUBKEY = TAWKAY.OpenSubKey(subkey); // subkey opens
SUBKEY = TAWKAY.OpenSubKey(subkey,true); // subkey not open shows error Requested registry access is not allowed
SUBKEY.SetValue("Some name", "1234567890");
Console.WriteLine(SUBKEY.GetValue("Some name").ToString());
}
else
{
Console.WriteLine("Cannot open registry");
}
Console.Read();
If I set OpenSubKey(subkey, true), it shows an error message Requested registry access is not allowed
Is there any permission needed to write into registry?
Please help me to solve the issue

Wow6432Node is not a real path in the registry. It is an alias for 32 bit keys in 64 bit OS.
You must use RegistryView.Registry32 in order to specify you want to work with 32 bits.
RegistryKey reg32key = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32);
RegistryKey reg_32bit_AppKey = reg32key.OpenSubKey(#"SOFTWARE\Program\SubProgram");
if (reg_32bit_AppKey != null)
{
// Here you can work with "SOFTWARE\\Wow6432Node\\Program\\SubProgram "
}

Modifying/deleting/adding keys in HKLM requires administrator rights.
In that case you want to do that you will need to change your applications manifest requestedExecutionLevel value to requireAdministrator

It is better to use "Reg" command inorder to perform any operation on registry.
Even though if you want to access the registry of remote machine you don't nedd credentials of that machine, having the machine name is sufficient.
For more information about "REG" command refer to the following link
http://technet.microsoft.com/en-us/library/cc732643(v=ws.10).aspx

Issue in accessing the registry programmatically

I have a issue reading a registry value programmatically using C#.
I looked into many sites and help but could not find any helpful.
I am able to access and read registry when I run VS in eleveated mode, but face issue when I run VS with out elevated mode.
Initially I started with the below code
byte[] val = (byte[])Registry.GetValue("HKEY_LOCAL_MACHINE\\Software\\MyServices\\Identity\\ASPNET_SETREG", "ValueName", 0);
This worked fine with elevated mode, but fails in non elevated mode.
Placed the attribute on top of the function
[RegistryPermissionAttribute(SecurityAction.Demand,Unrestricted=true)]
This did not help. Then Tried
[System.Security.Permissions.SecurityPermission(System.Security.Permissions.SecurityAction.LinkDemand, Flags = System.Security.Permissions.SecurityPermissionFlag.AllFlags)]
Still did not work.
Now I Tried the below code...
RegistryKey key = Registry.LocalMachine;
RegistrySecurity rs = new RegistrySecurity();
rs = key.GetAccessControl();
string user = "DomainName\\Username";
rs.AddAccessRule(new RegistryAccessRule(user,
RegistryRights.ReadKey,
InheritanceFlags.None,
PropagationFlags.None,
AccessControlType.Allow));
key.SetAccessControl(rs);//Exception: "Attempted to perform an unauthorized operation."}
//RegistryKey key2 = key.OpenSubKey("Software\\MyServices\\Identity\\ASPNET_SETREG");
//RegistryKey key2 = key.OpenSubKey("Software\\MyServices\\Identity\\ASPNET_SETREG", false);
//RegistryKey key2 = key.OpenSubKey("Software\\MyServices\\Identity\\ASPNET_SETREG", RegistryKeyPermissionCheck.ReadSubTree);
RegistryKey key2 = key.OpenSubKey("Software\\MyServices\\Identity\\ASPNET_SETREG", RegistryKeyPermissionCheck.ReadSubTree, RegistryRights.ReadPermissions);
Commenting SetAccessControl and use any of the OpenSubkey option, I get Exception: "Requested registry access is not allowed."
I am badly stuckup and unable to proceed.

private RegistryKey keyR = Registry.CurrentUser.OpenSubKey("Software\\YourKey",true);
private RegistryKey keyW = Registry.CurrentUser.CreateSubKey("Software\\YourKey");
public string version
{
get { return keyR.GetValue("VERSION", "", RegistryValueOptions.DoNotExpandEnvironmentNames).ToString(); }
set { keyW.SetValue("VERSION", value, RegistryValueKind.String); }
}
I am using windows registry in this way. No problem...

The windows registry is basically a structured file system, and has permissions for keys and values.
You do not have the permissions set correctly on ...\MyServices\ or deeper keys - you have no permission to access those from your unprivileged process.
Either:
Those keys should be readable by anybody, so you should change the permissions to make them readable by everybody. Or -
Those keys were intentionally restricted for a good reason, and so they should not be readable by everybody, in which case your program should always run elevated.

C# Create Values in Registry Local Machine

The following code is not working for me:
public bool createRegistry()
{
if (!registryExists())
{
Microsoft.Win32.Registry.LocalMachine.CreateSubKey("Software\\xelo\\");
Microsoft.Win32.Registry.LocalMachine.OpenSubKey("Software\\xelo").SetValue("hostname", (string)hostname, Microsoft.Win32.RegistryValueKind.String);
return true;
}
else
{
return updateRegistry();
}
}
Exception:
System.UnauthorizedAccessException | "Cannot write to the registry
key"

Non-admin and unelevated admin users don't have rights to modify the HKEY_LOCAL_MACHINE key. Run the program 'as administrator'.

Below code to create key in the registry.
Microsoft.Win32.RegistryKey key;
key = Microsoft.Win32.Registry.LocalMachine.CreateSubKey("Software\\Wow6432Node\\Names");
key.SetValue("Name", "Isabella");
key.Close();

Even when admin I don't think you can create new keys off LocalMachine. Make sure that you do
Registry.LocalMachine.CreateSubKey(#"SOFTWARE\YourCompanyName\SomeNewKey");
and not
Registry.LocalMachine.CreateSubKey("SomeNewKey");

Well you've got your answer already - I'm guessing you're running on Vista or Windows 7 (or Server 2008) and the process/user running the app doesn't have rights/permission to modify the registry.
So its not a code problem as such but a systems admin one. Build the app and run as administrator and see if that works.

Set the Premission Check bit to true...
Microsoft.Win32.Registry.LocalMachine.CreateSubKey("Software\\xelo\\", true);
:)