The remote certificate is invalid according to the validation procedure.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Security.Authentication.AuthenticationException: The remote certificate is invalid according to the validation procedure.
I am getting this error message when calling CampaignMonitor API
If any one know about that [please guide us.
You should now have received an answer to this via the support request you sent us, but I'll post what I said to you in case anyone else reads this post, and possibly has anything further to add.
I wasn't able to reproduce your problem, and since we haven't had many similar complaints, I'm guessing the problem is at your end. However, I've done a little bit of research for you.
I found this blog post, that might be helpful. http://weblogs.asp.net/jan/archive/2003/12/04/41154.aspx. One way to test to see if this is your problem is to browse via a web browser on your server to https://api.createsend.com/api/api.asmx?op=Subscribers.GetActive, and enter in your details and submit. If the browser pops up a dialog for you to accept a certificate, then you will most likely need to implement the solution in the blog post.
Let me know how you get on. Feel free to get back to us if you have any other problems or questions.