Type does not match the valueKind Microsoft.Win32.Win32RegistryApi.SetValue

Question

I have this code snippet where i am trying to write in the registry of windows so that i can expire a trail application.

    public RegistryKey rootKey;
    public RegistryKey regKey;
    public long expiry;
    // Use this for initialization
    void Start()
    {
        int period = 21; // trial period
        string keyName = "/Datefile.txt";
        long ticks = DateTime.Today.Ticks;

        rootKey = Registry.CurrentUser;
        regKey = rootKey.OpenSubKey(keyName);
        if (regKey == null) // first time app has been used
        {
            regKey = rootKey.CreateSubKey(keyName);
            expiry = DateTime.Today.AddDays(period).Ticks;
            regKey.SetValue("expiry", expiry, RegistryValueKind.QWord);
            regKey.Close();
        }
        else
        {
            expiry = (long)regKey.GetValue("expiry");
            regKey.Close();
            long today = DateTime.Today.Ticks;
            if (today > expiry)
            {
                Debug.Log("Application has expired.");
                Application.Quit();
            }

        }
    }

But it is giving me this error

 ArgumentException: Type does not match the valueKind Microsoft.Win32.Win32RegistryApi.SetValue . . . 

Even i have tried to set Object in this line but it producing the same error

 regKey.SetValue("expiry", new Expiry(), RegistryValueKind.QWord);

Answer 1

This is only valid for DWord which is 32 bit.

You are trying to put long value into a 32-bit binary number. Which is not going to work.

You can cast the long to unsigned int.

regKey = rootKey.CreateSubKey(keyName);
expiry = DateTime.Today.AddDays(period).Ticks;
var uintVal = (uint)expiry;
regKey.SetValue("expiry", uintVal, RegistryValueKind.DWord);
regKey.Close();

Now when converting back you just:

long myTicks = Convert.ToInt64(myRegValue);

Edit:

Behind the scene QWord is stored as string, you can try to store it as string directly but I suspect this is not your problem

void Start()
{
    int period = 21; // trial period
    string keyName = "/Datefile.txt";
    long ticks = DateTime.Today.Ticks;

    rootKey = Registry.CurrentUser;
    regKey = rootKey.OpenSubKey(keyName);
    if (regKey == null) // first time app has been used
    {
        regKey = rootKey.CreateSubKey(keyName);
        expiry = DateTime.Today.AddDays(period).Ticks;
        regKey.SetValue("expiry", expiry.ToString(), RegistryValueKind.String);
        regKey.Close();
    }
    else
    {
        var s = regKey.GetValue("expiry").ToString();

        expiry = long.Parse(s);
        regKey.Close();
        long today = DateTime.Today.Ticks;
        if (today > expiry)
        {
            //Debug.Log("Application has expired.");
            //Application.Quit();
        }

    }
}