Get information about LiveId (Office 365) account logged in Office application in VSTO AddIn

Question

I develop VSTO add-in for Word, Excel etc. And I need to get information about user currently logged in Office application. I need at least an email address.

I found these properties Globals.ThisAddIn.Application.UserName, .UserInitials and .UserAddress. But it's not about LiveID account. It is about office user settings.

How can I get required information?

Answer 1

I found only one way to retrieve this information - read the Registry... There are key HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Common\Identity\Identities\ if it is Office 2016. There are subkey like xxxxx_LiveId where xxxxx matches to ProviderId value.

You can read at least EmailAddress value from that subkey.

So I wrote some C# code for retrieve an e-mail address of logged in LiveID user:

string GetUserEmailFromOffice365()
{
    string Version = "16.0"; //TODO get from AddIn
    string identitySubKey = $@"Software\Microsoft\Office\{Version}\Common\Identity\Identities";

    using (var key = Microsoft.Win32.Registry.CurrentUser.OpenSubKey(identitySubKey))
    {
        if (key != null && key.SubKeyCount > 0)
            {
                foreach (var subkeyName in key.GetSubKeyNames())
                {
                    using (var subkey = Microsoft.Win32.Registry.CurrentUser.OpenSubKey($@"{identitySubKey}\{subkeyName}"))
                    {
                        object value = null;
                        try
                        { 
                            value = subkey.GetValue("EmailAddress");
                        }
                        catch (Exception ex)
                        {
                            Debug.WriteLine(ex);
                        }
                        if (value != null && value is string)
                        {
                            return value as string;
                        }
                    }
                }
            }
    }
    return null;
}

Of cource you shouldn't hardcode Version value. You can get and remember office version from Globals.ThisAddIn.Application.Version in ThisAddIn.cs file in ThisAddIn_Startup method.