I've just begun the "creating posts, polls, and questions" module on Trailhead. I have progressed to the part where you're supposed to post something via Chatter. However, my issue is that, I'm not able to type anything in the textbox.

I can see the Post, Poll, and Question tabs. Therefore, it doesn't appear to be a layout issue. When I attempt to click in the field my mouse cursor changes to a red "no" symbol and the "post" button is greyed out. This prevents me from typing anything in the field.

I have checked in Setup and Chatter is enabled. I am using the Lightning layout, Summer '17 release, and Google Chrome as my browser.

Any ideas?

I'm working on Service Cloud Basics module, Part 2: Automate Case Management on Trailhead. I'm on instruction #7 in the Add an Auto-Response Rule section. It's requesting that I add an email address to the form to be used as the "from" field on an email auto response. However, I'm not able to save the form becuase the email address that I've provided "is an invalid From email address." I've entered "support@somewhere.com" which, I believe, is a properly formatted email address. I'm guessing that it has to do with it being a non-verified "organization-wide email address" in my SalesForce instance.

Well I've added this ficticious email to my "organization-wide email addresses" but didn't realize that it needs to be verified. I don't own the "somewhere.com" domain to access and verify this email address. Do I really have to use a valid email account? Did I miss something?

The trail doesn't mention this requirement. This is my first foray into Sales Force and I had to poke around a bit to figure this out. Would be helpful if it had you add a VALID email address first.