System.Windows.Forms.SendKeys.SendInput >> Access denied at Task Scheduler

Question

I got a fuzzy problem, here is the following setup.

I got a small C# application to login to a certain website on a daily basis with a task scheduler on a Windows 2012R2 Server.

Here is the HTML login snipet:

<div class="control-group row-space-1">
<input class="decorative-input" id="signin_email" name="email" placeholder="Email Address" type="email" />
</div>
<div class="control-group row-space-2">
<input class="decorative-input" id="signin_password" name="password" placeholder="Password" type="password" />
</div>

<div class="clearfix row-space-2">
<label for="remember_me2" class='checkbox remember-me'>
<input type="checkbox" name="remember_me" id="remember_me2" value="true" class="remember_me"/>
Remember me
</label>
<a href="/forgot_password" class="forgot-password">Forgot password?</a>
</div>

<button type="submit" class="btn btn-block btn-primary large btn-large padded-btn-block">
Log In
</button>

The application has a Form.WebBrowser which opens a website with a user and password field. The application checks for a attribute and send enter to login. Here the code snipet:

HtmlElementCollection tagsColl=webBrowser1.Document.GetElementsByTagName("input");
foreach (HtmlElement currentTag in tagsColl)
{
    if (currentTag.Name.Equals("email"))
        currentTag.SetAttribute("value", username);
    if (currentTag.Name.Equals("password"))
        currentTag.SetAttribute("value", password);
    currentTag.Focus();
    SendKeys.Send("{ENTER}");
}

The application works totally fine when Im running it manually.

About the task scheduler setup. I tried a lot of different setups, have a look here:

Account:
local\Administrator
=> Error: Access denied

[x] Run only when user is logged in
=> Error: Access denied

[x] Run weather user is logged in or not
=> The Form with the WebBrowser doesent appear, I can see the task running in the task manager but nothing happens

[x] Run with highest privilegs
=> No effect

Configure for: Windows Server 2012 R2

When the task scheduler running the job I always got the following exception.

Error: Access denied

************** Exception Text **************
System.ComponentModel.Win32Exception (0x80004005): Access is denied
at System.Windows.Forms.SendKeys.SendInput(Byte[] oldKeyboardState, Queue previousEvents)
at System.Windows.Forms.SendKeys.Send(String keys, Control control, Boolean wait)
at System.Windows.Forms.SendKeys.Send(String keys)
at airbnblogin.Form1.autofill(String username, String password)
at airbnblogin.Form1.<main>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---

I guess it is because the Windows User is not logged in probably so it cant input the strings.

So here is my question, how can I come around this problem? Im open for every suggestion/further explanation!

Answer 1

This one works!

tagsColl = webBrowser1.Document.GetElementsByTagName("button");
        foreach (HtmlElement curElement in tagsColl)
        {
            if (curElement.GetAttribute("submit").Equals(""))
            {
                curElement.InvokeMember("click");
            }
        }

Answer 2

You can easily avoid the SendKey method by using the click event of the button of the login form. To follow your coding style with a button with id "submit":

HtmlElementCollection tagsColl=webBrowser1.Document.GetElementsByTagName("input");
foreach (HtmlElement currentTag in tagsColl)
{
    if (currentTag.Name.Equals("email"))
        currentTag.SetAttribute("value", username);

    if (currentTag.Name.Equals("password"))
        currentTag.SetAttribute("value", password);
}

HtmlElement button = webBrowser1.Document.GetElementById("submit");
if (button) button.InvokeMember("click");