There is a possibility of outlook not making the plug-in active after the update.
Please check the following:
1. Go to File>Option>Add-ins.
2. You should see “Vast Conference Outlook Add-in” under “Inactive Application Add-ins” if so click on Go at the bottom.
3. On the “COM Add-ins” window look for “Vast Conference Outlook Add-in” and check the box then OK.
4. Once this is completed you should see the Vast buttons in the ribbon.