Loop through the below folders and delete each file.
string _tempInetFile = Environment.GetFolderPath(Environment.SpecialFolder.InternetCache);
string _cookies = Environment.GetFolderPath(Environment.SpecialFolder.Cookies);
string _history = Environment.GetFolderPath(Environment.SpecialFolder.History);
List<string> folderPathList = new List<string> { _tempInetFile, _cookies, _history };
foreach(string dirpath in folderPathList)
try
{
Directory.Delete(dirpath, true);
}
catch{}