POST
You can post on the main feed. On the top of the homepage you'll see the blue navigation bar, click "feed" and post like you would on Facebook or Twitter.
LOGIN ISSUES
TRAC is built on Salesforce so you can technically get to the underlying objects directly in the Salesforce platform. If someone sends a direct link, it redirects the new user to log-in which and will take them to Salesforce. Users must use http://trac.sps.columbia.edu to log in. They will be redirected to a Salesforce log-in page that aligns with their setup (i.e. Lightning or Classic). They should use the "Log in to TRAC & Salesforce" button which will prompt them for their SSO credentials. This will lead them to the Intranet. Chantal