Community user cannot access Notes and attachments : solution

Users with customer community license was unable to access attachments and notes on a record which is not owned by the particular user,

Previously we had a staging object/record to transfer the attachments attached by the community user and transferred all the attachments from the staging object to related contact on an after update trigger.
However this solution started giving heap size exceeded error when try to transfer multiple attachments through.

Thanks to Spring 16 release now the issue is resolved, what you have to do is contact salesforce support and enable the feature

Please see the release notes link : https://releasenotes.docs.salesforce.com/en-us/spring16/release-notes/rn_networks_notes_attachments_ccp.htm