Ruthie,
When checking the email history of the bouncing member, & seeing that
recent messages have been successfully delivered, how can I reactivate
this member as a regular member?
I don't think you can directly reactivate them. But you can send a "bounce probe" - a notice to the member which will remove them from bouncing (blue or red) status if the member responds to the notice. Use the Actions menu at the bottom of the list, or click on the member's row and click on the button at the bottom of their page.
That said, the system is designed so that you generally don't need to do anything about these members - reactivating them is automatic, if they respond at all to the automatic bounce probes, and removing them is completely optional.
Also at what point should i consider a member ¡°dead¡±, after multiple
bounce probes & no change with their email delivery?
Yes, as J said, that's what the change from blue to red B status signifies: Groups.io has exhausted its attempts to get a response from the member.
One advantage of sending a message direct from your email, as Paul suggested, is that a direct message may be less likely to land in the member's Spam folder. But I understand with that many members bouncing why you find that impractical.
With a group of that size I think I would either:
1) Ignore bouncing members unless one asks for help. Then send them a bounce probe and also send a message from my email telling them to go look for the probe notice.
Or
2) Simply remove all members that have gone to red status.
Myself I generally choose (1) because I see no need for me to spend any extra effort on dead email addresses.
Shal
Shal Farley