re :folder that doesn't have a delete option in its dropdown menu.

All default folders which are required for the basic functionality do not have a delete option. eg: Inbox, Drafts, Templates, Sent, Archives, Junk, Trash

Any folder you create should have a delete option.

If this is an imap mail account then you can try this: Right click on the imap mail account name folder in Folder Pane and select 'Subscribe' Then just select the folder you want to unsubscribe from seeing and click on 'Unsubscribe' click on 'OK'

Then logon to your webmail account via a browser. Locate the folder and see if there is an option to not show in imap.

re :I also have folders that I have compacted by misstake.

All folders (especially Inbox. Drafts and Junk) should be compacted periodically to remove all old traces of 'moved' or previously 'deleted' emails. It tidies up the file and reduces the risk of loss of emails. It is basic housekeeping. So there is no 'mistake' in allowing compacting. 'Compacting' is not to be confused with 'Compressing'. Nothing has been compressed eg: zipped. See info about 'Compacting':

• https://support.mozilla.org/en-US/kb/compacting-folders

Did you use the manual compact option? Right click on folder and select 'Compact'

Or did you get an auto prompt to perform 'Compacting' ?

Why do you think it was a mistake to compact ? What is the problem?

Thank you for your feedback. I'm just an email user so I don't know all the details regarding configurations, setups, etc. I keep my emails organized in folders and subfolders. Somehow a couple folders have changed. Their icon is no longer a little folder but what looks like a portrait document. These folders no longer have a option to delete. (I sometimes delete folders that are no longer needed). I suspect (not sure) that I may have inadvertedly compacted or compressed (don't know or understand the difference) them. I can see the emails within these folders but I can't delete the folder or return it to is "folder icon" state. I have deleted the contents of these folders but I can't delete the folder itself. Perhaps a phone call or zoom chat is possible?

gfc

re : Somehow a couple folders have changed. Their icon is no longer a little folder but what looks like a portrait document. These folders no longer have a option to delete.

Sounds like a folder you created has been set up as the default folder eg: Drafts or Templates. First check these settings:

• Menu icon > Account Settings

It opens in a new tab.

• Click on 'Copies & Folders' for the account.

This is the place where you can choose which folder is the default folder for various purposes. Note if have an imap mail account you will need to select the name of the folder which is used by the server.

It is normal to choose the following:

• Select 'Place a copy in'
• If pop account select 'Sent folder on' and choose that mail account -email address.
• If imap account select 'Other' and choose 'Sent on account email address'. Note the 'Sent' will be the server name so it might be 'Sent Mail' or 'Sent Items'

Message Archives

• Select 'Keep message archives in'
• If pop account select 'Archives folder on' and choose that mail account -email address.
• If imap account select 'Other' and choose 'Archives on account email address'.

Drafts and Templates: keep draft messages in

• If pop account select 'Drafts folder on' and choose that mail account -email address.
• If imap account select 'Other' and choose 'Drafts on account email address'.

keep message templates in:

• If pop account select 'Templates for on' and choose that mail account -email address.
• If imap account select 'Other' and choose 'Templates on account email address'.

Go through your settings and make sure they are correct.

Tell me if you had to make some changes.