Problem With Google Groups

Hi! I am having a problem with Google Groups not allowing me to respond to threads. The Post button doesn't display, and, when I press th More icon, I am told that I don't have permission to reply to the thread. What gives?

 

1. Sign in to Google Groups.
2. Click the name of a group.
3. Click the message you want to read.
4. You can reply to the group or individually:
   • To reply to the group, below the message text, click Reply all. Compose your reply --> click Post Message.
   • To reply only to the person who posted, below the message text, click Reply to author. Your browser opens your configured email client to the message compose screen. Compose your reply --> click Send. This option is only available if:
     • You’re using a Google Account.
     • You have browser configured to open mailto links.
     • You have the Who can view member email addresses permission.
   • To forward a message, below the message text, click Forward. Enter some message text --> click Send.

 

I already apply to the groups, but the Post Message doesn't usually appear.

 

I have a Google account and am using the new version. I prefer the old version, though.