and the sendmailR package

In 2015 there was a issue raised in the Shiny Google Group about sendmailR not working on shinyappsio:!topic/shinyapps-users/3PTjZ0dvehg

It still doesn't work. The on-screen message is "ERROR: An error has occurred. Check your logs or contact the app author for clarification."

The logs stop without an error message.

I have created a multi-page, multi-user skeleton for Shiny apps with user login. I need email to verify user email addresses.

Are there any workable options here, like a paid shinyappsio account or a different sendmail package?


While the sendmailR package should work fine in Shiny Server, it will definitely not work on

In more detail, does not prevent users from sending e-mail using their own provider. Meaning, you can connect to MailChimp, Mailgun, or any other SMTP email service. However, we do not provide e-mail sending ourselves and the Unix sendmail program (which sendmailR wraps around) is not configured to leave the host it is running on, so you won't be able to use that (no matter which tier of you have).

Hope this helps!

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If you are looking for another solution, this is a gist on using the Mailgun service:

You need an account on Mailgun for it to work, but thats free up to 10k emails a month. You need to register a domain to send from too if you want to send off a whitelist.

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