Very strange issue I have just encountered on my setup. I don't know if a plugin is causing this or how long it has been here as I have been denying access to the dashboard all together.
I am now testing the dashboard with user accounts to see what they would see once I do allow them there.
Right now, I am using multisite user management plugin to have every new user set up as an "Author" on the main site in the network. Using the WP User FrontEnd plugin this works great because they are then allowed to post on front end
However, in the back end any user role of "Author" is not seeing the Posts menu on the left hand side of dashboard. Further, if I navigate directly to add post from URL it says I do not have sufficient privileges.
Stranger is the fact then when editing the user role to "Contributor" the Add Posts menu comes back with sufficient permissions. What could be causing this?
I deactivated plugins such as WP User Front End to see if it could be causing it but that wasn't it. I am totally confused!