System.ArgumentNullException: Value cannot be null. Parameter name: input at System.Text.RegularExpressions.Regex.Matches(String input) at System.Text.RegularExpressions.Regex.Matches(String input, String pattern, RegexOptions options) at ASP.smscwebservice_bulk_aspx.GetTLDUrls(String strInput) in D:\Websites\SMSCountry\SMSCwebservice_bulk.aspx:line 1335 at ASP.smscwebservice_bulk_aspx.Page_Load(Object sender, EventArgs e) in D:\Websites\SMSCountry\SMSCwebservice_bulk.aspx:line 55