Workflow cannot send E-Mails, but Sharepoint can

Question

I made a Workflow with the very first step to send me an e-mail. The next step is to set the workflow state from (unset) to something else.

When I look at the workflow-state in SharePoint, it says the workflow was started and the "state"-field is still empty. I conclude, that it doesn't get past the first step.

However, I get notifications and other mails from SharePoint, so the basic functionality works.

//edit1:

Mail address wrong: I did not enter the mail-address manually. I entered the persons name ("selected users") to send the mail to and sharepoint designer recognized it. It's an Office365-package, so I think it get's the names and addresses from exchange. The workflow also includes a "assign task"-action which also sends a mail and which also does not work.

Privileges: How can I see the privileges the workflow is run with? I created it by opening the site in sharepoint designer and logging in with my username. I am not administrator of sharepoint, but since it's a playground site, everybody has all privileges there.

Unrelated to these issues, I think a workflow should never just hang indefinitely like this? Nothing has happened in the last two days, it still has not progressed past the first action.

Answer 1

Check if mail address is correct and add after send mail action Log, run workflow and check if in state there is log message.

Answer 2

So, after quite some time, MS Support answered that the issue is the following:

The site I want to build a workflow in was originally created in BPOS-S and later migrated to SharePoint Online. The SharePoint App model uses the OAuth standard to authorize apps to communicate with SharePoint. OAuth requires that relying parties identify themselves with a unique name or domain information for the service principal host. SharePoint Online is configured to support the default organization domain names as a valid service principal host name, as in the following example: *sharepoint.com. In this situation, any site whose URL has a suffix that reflects a default organization domain name can authorize requests from applications.

Sites that were originally created in BPOS-S but that were later migrated to SharePoint Online don't have a default organization domain name. Instead, they use a domain such as contoso.sharepoint.microsoftonline.com.

Requests that use such a domain host name can't be authorized, and hosted apps can't communicate with content inside the domain. SharePoint 2013 Workflow Manager relies on communication with outside services that use the app model. Therefore, Workflow Manager also cannot communicate with content inside sites that were migrated from BPOS-S.

To work around this issue, it was necessary to create workflows on sites that weren't migrated from BPOS-S to Office 365. So I created a new site to build my workflows in and - like magic - it just works there.