Mail Archiver uses session logs to roughly capture what the app is doing. When there is a problem I get information where the problem is and what the problem is about.

The text below is gibberish for you, but it tells me that there is a problem when doing a drag-and-drop inside the list of mailboxes:

2019-12-21, 9:17:16 AM -------------------------
2019-12-21, 9:17:16 AM An error happened:
2019-12-21, 9:17:16 AM Class/Method: CCMailboxList.LBMailboxes.DropObject
2019-12-21, 9:17:16 AM Time: Saturday, December 21, 2019 9:17:16 AM 282541
2019-12-21, 9:17:16 AM Type of Error: NilObjectException
2019-12-21, 9:17:16 AM --------------------------
2019-12-21, 9:17:16 AM Stack:
2019-12-21, 9:17:16 AM
Function AppleListbox.DragRowInternal(int64, int64) as boolean
Function AppleListbox.Event_DragReorderRows(int64, int64) as boolean
Sub Application._CallFunctionWithExceptionHandling()
2019-12-21, 9:17:16 AM Stack done

Very rarely the session logs don't give enough or the correct information. Then we can use the Console.

In former times the Console contained warnings and issues. Nowadays, the Console mostly consists of chatter. We need to make sure that we don't get too much information.

Start the Console:

Start the Console

If you just let the Console open you will see much information. At any time you can click the Clear button to get rid of everything.

Now add a filter for Mail Archiver:

Normally, you would do the filter first and then start Mail Archiver. Here I had started Mail Archiver first.

Now do what causes the problem. Do a Cmd-A to capture the information from the Console. Then copy the data and paste the data into a fresh TextEdit document:

Save the document and send it to me.

That's how to use the Console to get more information about hard to solve problems.