How to fix this issue?
Calendar list is Missing in SharePoint 2010.
The required "site feature" may not be
activated in the SharePoint portal.
- Go to the "Site Settings"
- Go to "Manage Site Features"
- Check "Group Work Lists" feature is
activated or not. If not, Activate
If you are not able to view / create lists or
document library or task library, you need to activate the "Team Collaboration
Lists" site feature.