Hi @Katie Yance
Is this channel a standard channel or a private channel or a shared channel?
You can refer to this screenshot for how to distinguish what type a channel is (General and Public are standard channels):
I have had a little success and adding them back to the channel under a new email address but for a specific case that is no longer working.
Would you please clarify more on "but for a specific case that is no longer working."?
When adding the guest, does it show any error message, or it shows cannot find the user?
Or the guest can receive the invitation email but he is still not able to access the channel content.
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