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((JavascriptExecutor)driver).executeScript ("document.getElementById('fromDate').removeAttribute('readonly',0);"); // Enables the from date box
WebElement fromDateBox= driver.findElement(By.id("fromDate"));
fromDateBox.clear();
fromDateBox.sendKeys("8-Dec-2014"); //Enter date in required format
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((JavascriptExecutor)driver).executeScript("document.getElementById('fromDate').setAttribute('value','10 Jan 2013')")