Mailbox sync

We would like to implement your example “Create HelpDek on SharePoint 2013 Online” (from some time ago in CodeProject).
We are trying to read the incoming mails from a shared mailbox into a discussion list.
I cannot figure out what the correct syntax must be for the Sync statement (or how to enter it).
We now have:
Sync %Variable: supportMail%] to ICT discussions (with supportMail set as “support@xxxxx.cc”).

Although SharePoint Designer shows no error in checking, sometimes it shows an exclamation mark (This action has required parameters that are missing).
When we run the workflow it stops with this message:
System.Activities.Statements.WorkflowTerminatedException: InternalServerError Internal Server Error

Hello,

Please pay attention that usually shared mailbox looks like SMO-WebName@yourdomain.onmicrosoft.com. Also, you can try to use IMAP version to sync emails.