I have configured the archive mails in the Archive folder for the account, and under 'Options' I have selected 'A single folder' and ticked 'Keep existing folder structure...' When launching an archive action, the folder structure is created properly and MOST of the mails are archived in the relevant subfolders, but some files are archived as if I had not checked the 'Keep existing folder structure...' but instead just selected 'Yerly archived folders'. It happens within same launch of the Archive action. I have tried to review the characteristics of the files that are properly archived in the folder tree and those archived according to year. I cannot figure out what is governing how the mails are archived. Am I missing something?