Unable to locate element exception - c#-4.0

Question

The exception
"{"Unable to locate element: {\"method\":\"xpath\",\"selector\":\"// > div[#class='item-content'][3]\"}"}"
The code
public static void Main ()
{
Login_FAM lgn = new Login_FAM();
Demat_Acount prg = new Demat_Acount();
lgn.Login();
prg.DematAdd();
}
// login.cs file //
public FirefoxDriver driver ;
public Login_FAM()
{
driver = new FirefoxDriver();
}
public void Login()
{
driver.Url = "http://180.211.114.147:97//Account/Login";
var usernameF = driver.FindElementById("UserName");
var passwdF = driver.FindElementById("Password");
var loginB = driver.FindElementById("btnLogin");
usernameF.SendKeys("harsh");
passwdF.SendKeys("harsh123");
loginB.Submit();
// Thread.Sleep(3000);
}
//demat_acount.cs file //
public FirefoxDriver driver;
public Demat_Acount()
{
driver = new FirefoxDriver();
}
public void DematAdd()
{
IWebElement pro = driver.FindElement(By.XPath("// div[#class='item-content'][3]"));
pro.Click();
if(pro != null)
{
pro.Click();
}
}
below is my HTML Code
<ul class="main-navigation-menu ng-scope" ng-controller="menuctrl">
<li ui-sref-active="active" class="active">
<a ui-sref="app.dashboard" href="#/app/dashboard">
<div class="item-content" style="padding-right:10px;padding-top:5px">
<div class="item-media">
<i style="font-size:20px" class="icon-Dashboard"></i>
</div>
<div class="item-inner">
<span class="title ng-scope">Dashboard</span>
</div>
</div>
</a>
</li>
<li ui-sref-active="active">
<a ui-sref="app.familydashboard" href="#/app/FamilyDashboard">
<div class="item-content" style="padding-right:10px;padding-top:5px">
<div class="item-media">
<i style="font-size:20px" class="icon-FamilyDashboard"></i>
</div>
<div class="item-inner">
<span class="title ng-scope">Family Dashboard</span>
</div>
</div>
</a>
</li>
<li ui-sref-active="active" class="open">
<a href="javascript:void(0)">`enter code here`
<div class="item-content" style="padding-right: 10px; padding-top: 5px">
<div class="item-media">
<i style="font-size:20px" class="icon-Profile2"></i>
</div>
<div class="item-inner">
<span class="title"> Profile </span>
<i class="icon-arrow" style="margin-top: 3px"></i>
</div>
</div>
</a>
<ul class="sub-menu" style="display: block;">
<li>
<li>
<a ui-sref="app.demataccount" href="#/app/DematAccount">Demat Account</a>
</li>
<li>
<a ui-sref="app.familyassociation"href="#/app/FamilyMemberAssociation">Family Association</a>
</li>
</ul>
</li>
</ul>
And FYI i have executed same code without creating methods and objects and that is working but crating method and objects it doesn't working

Answer 1

WebDriver could not find the element as your element is embedded in another div tag. Make sure your XPath is correct. Validate it using firepath. I'm new to automation, if I get this error, I'll verify my XPath.
Try changing XPath to
// div[#class='item-content'][3]/div/i
I'm not sure whether this might solve your problem or not, but trying to help. Make sure the element exists or put a wait until the element is visible.