Is there some clue as to which are not shown, like the ones gmail tags as important perhaps, or mail from older than a certain date? Or more than the 10,000 than yahoo have decided is enough in your IMAP client.

Thanks Matt for your feedback.

In regards to your question, I don't see any clues as to what the problem is.

I didn't set up any filters for my friend, I checked the settings and didn't see anything that I thought was out of place. I fiddled around for 1.5 hours and gave up, came here for help as I don't know what else to check out.

I am going to do a safe boot on her system which will force a disk check but other than that, this problem has stumped me.

I have Thunderbird installs on 2 other computers of mine and they work perfectly without any inbox issues like this. Don't understand why my inboxes work correctly while hers doesn't.

I will also ask her to keep a close watch on her inbox's behavior, maybe something will show up but if you or anyone else here have any other ideas, let me know.

Thanks, Gary

Two points.

1. You are using an operating system I am not familiar with. I have to extrapolate. But as only about 3% of Thunderbird users are on apple, finding someone who is familiar is a task. 2. Many quirks are provider dependent. You have not mentioned who the provider is.