TB is downloading emails from unsubscribed Yahoo group

[OldGrantonian]

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I hope the group can understand this post. In a single sentence, I want to stop using an email account for one Yahoo group, and use the same email account for a different Yahoo group.

In TB, I had one Yahoo group in one email account. Let's say group1 in email1.

Last night I unsubscribed from group1 using email1. Now I no longer see group1 in my Yahoo Groups list for email1 using my browser. Thats fine.

I then used email1 to subscribe to Yahoo group2.

As soon as I clicked on email1 in TB, all the old emails from group1 downloaded. Any emails in group1 that were added after I unsubscribed from group1 were not downloaded. So that's half good and half bad.

I could also see 2 emails from the new group2 that were added to group2 after I subscribed.

I decided to wait till this morning, and try again. That should have been enough time for the 2 groups to sort themselves out.

This morning, I deleted email1 from TB. I then re-added email1, and subscribed to group2, as before.

The results were identical to last night: I see new emails from group2 that were added after I subscribed to group2. Again, I see the old emails from group1 up till the time that I unsubcribed from group1. In the browser, I can see that more emails have been added to group1. So again that's half good and half bad.

My memory is no longer good, but I'm certain that when I first used TB about a year ago to subscribe to group1, I immediately got a lot of old emails downloading. That was fine, and expected.

Question: What do I need to do to see (a) all the old emails from group2, and (b) none of the emails from group1?

Thanks.

[tanstaafl]

"In a single sentence, I want to stop using an email account for one Yahoo group, and use the same email account for a different Yahoo group."

The simplest way would be to login to Yahoo using a browser and unsubscribe from the first Yahoo group and then edit the second Yahoo group to use the same email address that you used to use for the first Yahoo group. You wouldn't have to do anything in Thunderbird, unless you wanted to delete some of the already downloaded messages from the first group.