>I've been using Sergey's cdo2000.prg for some time now and it works great.
>
>https://www.berezniker.com/content/pages/visual-foxpro/cdo-2000-class-sending-emails
>
>Recently, however, I've started encountering random hangs. I added some logging code to figure out exactly where it was hanging and it's at:
>
>this.oMsg.SEND()
>
>The same computer will send hundreds of emails fine and then, for no discernible reason, it hangs at this line.
>
>The default timeout is 30 seconds but the hang is not releasing; my application has to be end-tasked.
>
>Any ideas?

A guess, but might it be limitations set by the SMTP server or ISP? Some have limitations such as:

- Total # of messages per hour and per day
- Total # of recipients per hour and per day
- Total size of messages per hour and per day

If you hit such a limitation you typically don't get any sort of error message or warning. I don't know how an SMTP server or ISP might respond to a perceived violation, but it's not impossible whatever they do could hang a SEND().

If you have a good relationship with the server owner or ISP you could ask them if they've logged any unusual events around the times you're seeing these intermittent errors.