Outlook App Missing

Hi,

The calendar app is missing in my  team sites when using a custom template.

The problem is while activating the SharePoint Server Publishing on a new Team Site.

I created a custom master template and have it applied on my site collection.

But if I activate the SharePoint Server Publishing on a new Team Site. All the Apps disappear from the team site.

I have the SharePoint Server Publishing, SharePoint Server Standard Site Features, SharePoint Server Enterprise Site Features and the Team Collaboration List Features Active in the Site Collection already.

Any idea what could be causing the calendar and the other apps no to be available when the SharePoint Server Publishing is activated? Any ideas or suggestion will be very appreciated.

Thank  you.