Collaborate on Excel workbooks with Sharepoint Foundation

Question

My company recently implemented SharePoint Foundation 2013 and our shared Excel workbooks are no longer allowing multiple users to collaborate at the same time. We have verified that all the settings and permissions are correct and that checking in and
checking out is not required. Is this something that is not available with SharePoint Foundation? We are using Office 2013 installed on the clients, not Office online. Thank you.

Answer 1

Co-authoring of Excel workbooks is only supported when all the editors are using the Excel web application, not the Excel client application.
From
Microsoft's overview of co-authoring in SharePoint 2013:
>"Co-authoring is easy to use from the end user’s point of view. When a user wants to work on a document in Word 2013, PowerPoint 2013, OneNote 2013, Visio 2013 or one of the Office Web Apps, he or she merely opens it from SharePoint 2013 or SharePoint
Online, as usual. If another user already has the document open, both users can edit the document at the same time.
One exception to this is that users can co-author in Excel Web App only if everyone uses the Excel Web App to access the workbook. If anyone uses Excel 2013 or Excel 2010 (the client application)
to access the workbook, co-authoring in Excel Web App will be disabled for that workbook while it is open in the client application."
>"The Excel 2013 client application does not support co-authoring workbooks in SharePoint 2013 or SharePoint Online. But, the Excel client application uses the Shared Workbook feature to support non-real-time co-authoring workbooks that are stored
locally or on network (UNC) paths."