It is recommended to post a sample code when you post any question may help community members to understand the issue and help to make a tests.
You said that you had modified some registry settings. I suggest you to reset those registries and reset IE browser again.
Try to use C# code example below may help to switch window.
//switch to new window.
driver.SwitchTo().Window(driver.WindowHandles.Last());
//if you want to switch back to your first window
driver.SwitchTo().Window(driver.WindowHandles.First());
Below is an C# example for switch to new window by comparing the title of the window.
protected static Boolean SwitchWindow(string title)
{
var currentWindow = driver.CurrentWindowHandle;
var availableWindows = new List<string>(driver.WindowHandles);
foreach (string w in availableWindows)
{
if (w != currentWindow)
{
driver.SwitchTo().Window(w);
if (driver.Title == title)
return true;
else
{
driver.SwitchTo().Window(currentWindow);
}
}
}
return false;
}
References:
(1) Selenium WebDriver in C#: Switch To new window or tab
(2) How can I switch to new window using webdriver?
(3) Selenium webdriver selecting new window c#
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