Thank you for all answers. I found solution to my problem. The last command was command which was linked with IFrame

WebElement editorFrame = driver.findElement(By.cssSelector("#sentmsgcomposeEditor_ifr"));
   driver.switchTo().frame(editorFrame);

   WebElement body1 = driver.findElement(By.tagName("body"));
   body1.sendKeys(Keys.CONTROL + "a"); 

So i was in IFrame actually because of it i couldn't find any element. I performed following command:

 driver.switchTo().defaultContent();

After that it is possible to find locators.

Try using CSS

WebElement element = new WebDriverWait(driver,30).until(ExpectedConditions.elementToBeClickable(By.cssSelector("a[id*='DERIVED_REGFRM1_LINK_ADD_ENRL'][class='SSSBUTTON_CONFIRMLINK']")));

NoSuchElementException happens generally in 2 scenarios.

1. Webelement locator is wrong. (which doesn't seems to be the situation in your case)
2. Your are trying to find the webelement even before it is loaded on the page.(This seems to be your problem)

To solve this you should wait till the webelement gets loaded on to the webpage.

One way to do this to use WebDriverWait Class. Sample snippet is below:

/* Initialize the WebDriverWait, with 30 seconds of wait time. */
WebDriverWait wait = new WebDriverWait(driver, 30);
wait.until(ExpectedConditions.visibilityOfElementLocated(By.name("locator_name")));

Your xpath expression:

WebElement query = driver.findElement(By.xpath("//html/body/div[2]/span/center/form/table/tbody/tr/td[2]/div/div/input"));

looks correct but if you still are facing the issue please check the correctness of xpath again. If it fails again increase the time for Wait as:

driver.manage().timeouts().implicitlyWait(20, TimeUnit.SECONDS);

or you can use explicit wait for the specific element as below:

WebDriverWait wait = new WebDriverWait(driver, 20);
wait.until(ExpectedConditions.visibilityOfElementLocated(By.xpath("//html/body/div[2]/span/center/form/table/tbody/tr/td[2]/div/div/input")));

Use linkText element Locator method instead of XPath.

    driver.get("http://awqaf.texpo.com/"); 
    WebDriverWait wait = new WebDriverWait(driver, 10);
    WebElement element =wait.until(ExpectedConditions.presenceOfElementLocated(By.linkText("ABOUT US"))); 
   // WebElement aboutdrop=driver.findElement(By.linkText("ABOUT US"));

Also, try with removing driver.switchTo().defaultContent(); this line.

Generally switchTo().defaultContent(); method is used to go back on previous working window. So if it requires in your case then & then you may use.

As mentioned in the comments, the slight difference between these two XPaths:

String columnsXpath = "(//div[@class=\" x-ignore x-menu x-component\"]//a)[3]";
String columnToDisplayXpath = "(//div[@class=\" x-ignore x-menu x-component \"]//div)/a[text()=\"" + column + "\"]";

besides the part at the end, is that the latter has a space after "component" and the former doesn't.

I suspect that the using normalize-space() and removing the leading and trailing spaces in the comparison values might help iron out inconsistencies in the spacing of the @class attribute value:

String columnsXpath = "(//div[normalize-space(@class) = \"x-ignore x-menu x-component\"]//a)[3]";
String columnToDisplayXpath = 
    "(//div[normalize-space(@class) = \"x-ignore x-menu x-component\"]//div)/a[text()=\""
    + column + "\"]";

Switch to the iframe first, for that try the below code.

driver.switchTo().frame(driver.findElement(By.cssSelector("iframe[src*=sfactory]")));

After that you can use the XPath or CSS selector to identify the locator.

css: a[onclick*=exitAction]

xpath: //a[contains(@onclick, 'exitAction')]

NoSuchElementException

org.openqa.selenium.NoSuchElementException popularly known as NoSuchElementException extends org.openqa.selenium.NotFoundException which is a type of WebDriverException.

NoSuchElementException can be thrown in 2 cases as follows :

• When using WebDriver.findElement(By by) :

  //example : WebElement my_element = driver.findElement(By.xpath("//my_xpath"));
  

• When using WebElement.findElement(By by) :

  //example : WebElement my_element = element.findElement(By.xpath("//my_xpath"));
  

As per the JavaDocs just like any other WebDriverException, NoSuchElementException should contain the following Constant Fields :

Constant Field      Type                                        Value
SESSION_ID          public static final java.lang.String        "Session ID"
e.g. (Session info: chrome=63.0.3239.108)

DRIVER_INFO         public static final java.lang.String        "Driver info"
e.g. (Driver info: chromedriver=2.34.522940 (1a76f96f66e3ca7b8e57d503b4dd3bccfba87af1),platform=Windows NT 6.1.7601 SP1 x86)

BASE_SUPPORT_URL    protected static final java.lang.String     "http://seleniumhq.org/exceptions/"
e.g. (For documentation on this error, please visit: http://seleniumhq.org/exceptions/no_such_element.html)

Reason

The reason for NoSuchElementException can be either of the following :

• The Locator Strategy you have adopted doesn't identifies any element in the HTML DOM.
• The Locator Strategy you have adopted is unable to identify the element as it is not within the browser's Viewport.
• The Locator Strategy you have adopted identifies the element but is invisible due to presence of the attribute style="display: none;".
• The Locator Strategy you have adopted doesn't uniquely identifies the desired element in the HTML DOM and currently finds some other hidden / invisible element.
• The WebElement you are trying to locate is within an <iframe> tag.
• The WebDriver instance is looking out for the WebElement even before the element is present/visibile within the HTML DOM.

Solution

The solution to address NoSuchElementException can be either of the following :

• Adopt a Locator Strategy which uniquely identifies the desired WebElement. You can take help of the Developer Tools (Ctrl+Shift+I or F12) and use Element Inspector.

  Here you will find a detailed discussion on how to inspect element in selenium3.6 as firebug is not an option any more for FF 56?

• Use executeScript() method to scroll the element in to view as follows :

  WebElement elem = driver.findElement(By.xpath("element_xpath"));
  ((JavascriptExecutor)driver).executeScript("arguments[0].scrollIntoView();", elem);
  

  Here you will find a detailed discussion on Scrolling to top of the page in Python using Selenium

• Incase element is having the attribute style="display: none;", remove the attribute through executeScript() method as follows :

  WebElement element = driver.findElement(By.xpath("element_xpath"));
  ((JavascriptExecutor)driver).executeScript("arguments[0].removeAttribute('style')", element)
  element.sendKeys("text_to_send");
  

• To check if the element is within an <iframe> traverse up the HTML to locate the respective <iframe> tag and switchTo() the desired iframe through either of the following methods :

  driver.switchTo().frame("frame_name");
  driver.switchTo().frame("frame_id");
  driver.switchTo().frame(1); // 1 represents frame index
  

  Here you can find a detailed discussion on Is it possible to switch to an element in a frame without using driver.switchTo().frame(“frameName”) in Selenium Webdriver Java?.

• If the element is not present/visible in the HTML DOM immediately, induce WebDriverWait with ExpectedConditions set to proper method as follows :

  • To wait for presenceOfElementLocated :

    new WebDriverWait(driver, 20).until(ExpectedConditions.presenceOfElementLocated(By.xpath("//div[@class='buttonStyle']//input[@id='originTextField']")));
    

  • To wait for visibilityOfElementLocated :

    new WebDriverWait(driver, 20).until(ExpectedConditions.visibilityOfElementLocated(By.xpath("//div[@class='buttonStyle']//input[@id='originTextField']")));
    

  • To wait for elementToBeClickable :

    new WebDriverWait(driver, 20).until(ExpectedConditions.elementToBeClickable(By.xpath("//div[@class='buttonStyle']//input[@id='originTextField']")));
    

Reference

You can find Selenium's python client based relevant discussion in:

• Selenium “selenium.common.exceptions.NoSuchElementException” when using Chrome