I rebooted and now sorting is working as expected. (Why didn't I think of that on my own?) Thanks, Brian.

Can message status be set using a filter?

Check out the Attribute rule type.

Thanks. This rule type filters for attributes. I am looking for a way to assign attributes.

I'm sorry.  I read your message but obviously didn't "read" your message.

AFAIK, the only options that affect attributes are mark message as read and mark message as significant which I'm sure you've already found in the list of actions.

Thanks for trying to help.

I wanted to set up a filter to mark as URGENT in the properties of selected messages so they are are shown at the top of the inbox. I've been doing that manually for each message. That's been working - until today when they are no longer sorted that way.

Any suggestions about this.?

Oh, I uninstalled and reinstalled 4.73 but that didn't cure the problem.

You might also check the folder sorting options.  While the new mail folder has focus go to the Folder pull-down menu item and review its settings.

If you haven't done a system restart since the problem started I suggest doing one.  I know that sounds absurd but it's really weird the odd behaviors I have encountered that have self-resolved with a restart.

FWIW, I keep messages that need attention on top by marking them as unread and having the "Sort unread before read" option enabled.

Finally, if you use Preview mode there is a setting to remember each folder's sorting mode separately.  I suspect you want that setting enabled.