[Evolution] EVO shows N-unread on left tho all messages actually read in msg list

[Dan Saint-Andre <saint grillongroup org>]

When I look at the left panel, I see there an inbox display  INBOX (N) in bold type.
This usually indicates the number of not read messages.

When I look at the center panel list of messages, I find zero message marked not read.
They usually appear with a bold subject and sender.

The mailbox is an IMAP account.  I tried Send/Receive to force a re-sync with the server.
The not read count did not change nor did more messages appear in the list panel.

How do I get the count to agree with the message list?

Merci d'avance,
~~~ 0;-/ Dan