Gmail keeps all your emails, incoming, sent, archived - everything is stored in 'All Mail'.

The only reason you see copies of those emails in eg: 'Inbox' and 'Sent' and any other imap folder is because gmail applies a kind of tag which gmail calls 'labels' to each email so it can be shown in any number of folders even symultaneously. It's a way of providing a more familiar view of folders . So really you have duplicated everything by subscribing to see 'All Mail'. Therefore 'All Mail' folder could be massive.

Is there some reason why you have subscribed to see 'All Mail'?

You could unsubscribe from seeing 'All Mail' if it is not required. right click on gmail account name in Folder pane and select 'subscribe' slect the 'all Mail' folder in list and clickon 'Unsubscribe' click on OK

There are also options to only download headers which might be an option for the 'All Mail' folder. right click on gmail account name in Folder pane and select 'Settings' select 'Synchronisation & storage' Assuming you have selected to 'keep messages for this account on this computer..... click on 'Advanced' button If you uncheck the 'All Mail' folder, then only headers get downloaded. Click on all OK's.

Oh wow, that's great! I never knew you could unsubscribe from certain folders. I never use the ALL MAIL folder at all, for anything, I just thought it was necessary to have there for everything else to function ok.

So do you think I can unsubscribe from that without causing any issues? I have a lot of folders and sub folders in some accounts to keep things organised properly, so would be shifting mails from inbox to other folders, so as long as it won't cause any issues, that'd be great. I'm guessing it would also reduce the overall size of the Thunderbird folder?

I'm ok with downloading the whole mail instead of just the headers, I used to download headers only, but found it much easier now just to display the whole thing immediately.

The all mail folders for the various accounts can have thousands of mails in them, so it might be best just to unsubscribe from it so there's not the random syncing of thousands of messages, even if they are just headers?

I'll take a backup first of the TB folder, but if you reckon I'm good to just uncheck the All Mail folder on each account, then that's brilliant!

Really appreciate the advice :)

Yes you can unsubscribe from seeing 'All Mail'.

It will still be in the webmail account as gmail uses it for everything. But it will not be visible in thunderbird.

Remember: when you delete an email from eg: inbox If you want it to get properly deleted then you need to make sure all deleted emails go into the subscribed gmail trash/bin folder. Gmail auto empty the Trash periodically approx every 30 days.

Any email in the gmail Trash will get deleted from 'All Mail'.

If the deleted emails do not use the gmail Trash then only the Inbox label is deleted and the actual email is archived in the 'All Mail' folder. So if your quota keeps going up then it could be because the emails are not being properly deleted.

Make sure you are subscribed to see the gmail Trash/bin folder. Make sure the gmail imap account 'Account Settings' > 'Server Settings' for 'when I delete a message' it uses 'Move to this folder' option and select the trash on gmail account.

ALSO same window...select to 'Clean up (expunge) Inbox on Exit' This will compact the Inbox folder removing any hidden marked as delted emails. See image as guide.

Thanks again for your continued input!

I'm happy to say, that on checking the server settings, each of the accounts I had was already set up to direct deleted messages to the bin on account@gmail.com :)

I don't actually delete too many emails, with spam, I tend to manually drag the to the spam folder, which I think gets emptied every 30 days or so too? But I had the idea that if I put it in SPAM, maybe it helps Google learn and filter out these emails for other users?

I'm not sure what happens when I press SHIFT and delete, which I actually do most times I delete something anyway... does it delete it completely from all mail too I wonder, or skips the bin and then ends up not deleting it from ALL MAIL too I wonder?

I didn't have the EXPUNGE option selected, but I think I recall having selected something to compact folders on a regular basis before (I think it was dictated by size of folder?), so is there need to click the EXPUNGE one too I wonder?

re :deleted messages to the bin on account@gmail.com

Sounds like your gmail Trash folder is actually called 'Bin'. So is mine.

re : SHIFT and delete....skips the bin and then ends up not deleting it from ALL MAIL too I wonder?

If emails are not going into gmail 'Bin' then you are only deleting the label; not the email. This means email disappears from eg: 'Inbox' and gmail will auto archive the email in 'All Mail'. It means you can easily reapply 'labels' so email can reappear in any folder of choice- great news if you deleted in error. Your server quota will not go down until emails are deleted from 'All Mail'. This is gmail's wonderful quirk on what is really deleted. It must be put in gmail 'Bin' if you really want it deleted and recover space on server.

re : I recall having selected something to compact folders on a regular basis before (I think it was dictated by size of folder?)

There is an option you can set which will run an automatic compacting on 'All folders' when you can save over x MB.

• Menu icon > Options > Advanced > 'Network & Disc Space' tab
• Under 'Disc Space' section.
• select checkbox 'Compact all folders when it will save over eg: 10 MB in total'
• click on 'OK

Recommended that you do not set the MB too high so compacting runs more frequently. This method is useful if you tend to filter messages into various folders on download and as a result will be deleting from several folders.

If you have most emails come into 'Inbox' and that folder gets a lot of deleting action, then it may be a good option to select the EXPUNGE option in Account Setting, so every time you exit the 'Inbox' gets cleaned up. Please note: after exiting Thunderbird there are background processes that are occuring, so I recommend you do not shut down computer too quickly, so allowing those processes to complete.

You can have both auto compact actons set up.

Thank you again! It's all set up and working very well now.

Thunderbird still hangs when I'm moving emails into a folder with 50,000 or so emails. I think I posted here before with the same issue and was told I should try split that folder into sub folders too, which I think is the reason I have a folder for say 2007-2009, 2010-2012 and so on and I think it speeds things up :)

Everything else going fine, and since unsubscribing from ALL MAIL on the accounts, the Thunderbird folder has since dropped a few GB in size too :)