As platform administrator you can choose whether to enable users post in their profiles or not.
Enter Admin Panel > GOconection and you will find the option Set Permissions.
By clicking on the checkbox, users are allowed to post on their profiles at the social wall. In case you do not click the checkbox, users will not be able to do publications in their profiles, but they can post at the spaces that you have configured with social activity.
Once the process is finished, click on save changes.