Error 56 While Sending an Email via SMTP Server

Updated Apr 9, 2019

Issue Details

I would like to send an e-mail using "Send Email using SMTP Client" shipped example. I entered all of the required input values including outgoing server address, login credentials and destination address. When I am trying to send the message the following error is showing up:
Error 56 occurred at
LabVIEW: (Hex 0x38) The network operation exceeded the user-specified or system time limit.


There might be several causes not allowing you to send the e-mail message. Perform the following operations in order to use SMTP:
  • Allow LabVIEW to get access to the internet and add firewall exception.
  • Check what is your actual internet connection status - directly ping the SMTP server through command prompt.
  • Make sure the following ports are opened in your local network: 25 (SMTP), 465 (SMTP over SSL), 587 (SMTP Submission).
  • Some of the mailbox providers by default blocks 3-rd party application access thought SMTP. Change these parameters in your mailbox settings if necessary.