Are you talking about an imap or pop mail account?

If imap: In Thunderbird, suggest you unsubscribe from seeing them and then logon to webmail account via a browser and delete them.

If pop: It may be quicker to do this via the profile name folder.

make hidden files and folders visible: http://kb.mozillazine.org/Show_hidden_files_and_folders

In Thunderbird

• Help > Troubleshooting Information
• click on 'Open folder' button

a new window opens showing the contents of your profile name folder.

• Exit Thunderbird now this is important.

• click on 'Mail ' folder to see contents.
• click on pop mail account name to see contents.

Files will have same name as the folder you usually see in the Folder pane. mbox files have no extension and they can contain emails. msf files are indexing files. there will be an msf file for each mbox file.

sbd folders mean there are subfolders for that folder. sbd folders can also contain mbox and msf files. If you want to delete everything in a sbd folder, you could delete the folder.

You can select several files and delete all at once. This is quicker than doing it via Thunderbird.

Be careful what you delete.

Thanks for your help. How do I find out if it is imap or pop mail account?

Regardless of that, when I right click on a single folder and it lights up in a blue colour I have the option to Delete it. But when I select a bunch of folders (in blue colour) and right click on them I do not get the option to Delete that selected bunch/group of folders. Nothing at all has changed except I am wanting to delete more than 1 folder but I am thwarted. I am assuming this is the same for everyone around the world using this software. For the life of me I cannot see why that simple ability is not available and what should be a simple and easy operation is turned into a specialist undertaking.

re :How do I find out if it is imap or pop mail account?

How to find out what type you are using:

• Right click on mail account in Folder Pane and select 'Settings'
• Select 'Server Settings' for the mail account.
• Top right it will say: 'Server Type'

It will either say 'Pop Mail Server' or 'Imap Mailserver'. Imap mail accounts also have 'Synchronisation & Storage' option.

If IMAP: How to unsubscribe from seeing folders:

• Right click on mail account in Folder Pane and select 'Subscribe'
• select/highlight all folders and subfolders you want to stop seeing (so you can delete them via webmail )
• click on 'Unsubscribe' button.
• click on OK

You can only delete one folder at a time via Thunderbird.

That's why I advised you on how to remove them en-masse. Exit Thunderbird and POP account files are deleted via Profile folders. This is so much easier and then you need to empty the recycle bin.

IMAP : Either you delete folder via thunderbird or delete via webmail. But if you delete via webmail, you need to unsubscribe from seeing them in Thunderbird first. When unsubscribing, you can select several by using the standard methods to select batches of folders or various folders. I'm not certain whether webmail offers a means of deleting several folders en-masse. It depends upon what is offered by that webmail account.