The IITG Newsgroup service has been replaced with the Office 365 groups, and we have created all the newsgroups currently available in IITG Newsgroups in Office 365 groups. We have created the new office 365 groups as public groups where users will be able to join and leave the group as they wish. Now, users will be able to send messages on these groups with access to their email service unlike IITG newgroups, where users are required a separate login to post messages. Users need to check the groups in the groups section for any message posted in the group. By default, users will not receive any mail in their INBOX, if you follow the group, then a mail will be sent to your inbox for any message posted in that group. 

To join the groups, please right click on Groups (found on the left pane) and select "Discover", then search the group that you want to join. After that, select the group and then click on join. After you have joined the group, it will appear on the groups section of your subscribed groups.