Can attachments be indexed when emails are populated into SP2013 via OnePlaceMail?
I dont seem to be able to search the content of email attachments when they are placed into SP2013 via OnePlaceMail
Yes, you should be able to search for attachments once they have been uploaded via OnePlaceMail.
This would be dependent on the search settings in SharePoint, in regards to crawl. Are you able to advise if you can find an item that has been previously uploaded\?