That is where her email messages are stored. If she has another drive besides drive C, the messages can be offloaded. Otherwise, she needs to remove some messages.

Could you tell me how to offload her old messages?

Would she still be able to access them? thanks

If she has a secondary drive available, that would work. Does she have another such drive? Is this a POP account?

No, it's an IMAP account, and yes she has an external drive. What steps should she take to move messages?

thanks

Okay, this is just some simple steps: - First, we want to COPY her email account to the other drive. click help>moretroubleshootinginformation, scroll down to 'profile folder' and click 'open folder'. Now, exit Thunderbird. You are now in Windows File explorer. - click the 'imapmail' folder and her account should appear. COPY that folder to the other drive. - Next, we want THunderbird to use the copied account. Start Thunderbird, click tools>accountssettings>account>serversettings. At bottom of pane, is Local Directory. Click the browse button to locate the folder on the other drive. Once done, close the folder. - Now, to confirm it works, close and restart Thunderbird and confirm that the account is working properly. - At this point the account remaining in profile in the imapmail folder on C drive may be deleted. You can repeat the first step above to get there and delete it.

Reminder: Her profile is still on drive C (all her settings, addressbook, etc) and that one account is on the other drive. Be sure to back up BOTH of them periodically. Thunderbird can backup profile with Tools>Export, by the account and messages on the other drive need also to be periodically copied to a backup source.

Is it a gmail account? Does there tend to be large attachments?

Hi David,

Thanks for your reply. I think your solution would work, but doesn't answer why the AppData folder is so big. My wife hasn't been archiving her emails, maybe that's the reason?

From your instructions I can move her account to an external drive, but I'd like to see if there's a way of reducing/clearing the size of the AppData folder for TB. Any thoughts on this?

thanks,

Hi Wayne

I'm using Fastmail but not gmail. I don't think there are large attachments but I can double check that.

thanks

It would help to know which folder is so big. If you click help>moretroubleshootinginformation, scroll down to 'profile folder' and click 'open folder', you will be in Windows File manager. Click the imapmail folder and then the accountfolder. From there, you should see folders for inbox, sent, etc. Right-click each and select 'properties' to see the size of each. Repeat the process for the Mail folder in profile to see if her large storage use is in local folders. Now you will know exactly what is the source of the problem, and from there a solution can be developed.

windirstat or treesizefree will answer the question more quickly.

Hi David, Thanks for your reply. I think your solution would work, but doesn't answer why the AppData folder is so big. My wife hasn't been archiving her emails, maybe that's the reason? From your instructions I can move her account to an external drive, but I'd like to see if there's a way of reducing/clearing the size of the AppData folder for TB. Any thoughts on this? thanks,

Exactly. If this was me, I'd want to know why AppData is so large. If I had to guess, it would be that windows search has been enabled - which would double the storage requirement.

Also, moving data to another drive is not a great first choice for solution - it introduces complexities and potential problems.

Lastly, archiving won't help, unless you save the messages outside of Thunderbird. Thunderbird's archive function doesn't do that.

I used the Treesize app to find the folders that (maybe) could be deleted. Please see image below.

The Verizon pop account is no longer in use. Could some of those folders go into Trash without losing messages from when the account was active?

thanks!

Well, the easiest savings might be that second profile of 13 gig. If you use one profile exclusively, then that second one shown lower in the screenshot could be deleted completely. If in doubt, MOVE it somewhere else for safety while Thunderbird is not running and delete it. I think that may give you a big immediate save. On your question, yes, folders that are not needed could be removed. I suggest moving them to Local Folders prior to deleting the Verizon account. Never delete until everything is working. So I suggest exiting and restarting THunderbird before finally deleting the Verizon account.

Also, that second profile (very likely) isn't even a profile any more - it is under the Thunderbird directory, not under the Profiles directory. And per Treesizefree the folders date to 8/2020, so it looks in 8/2020 someone made a backup by copying the entire profile up one directory level.

But as for the Verizon account, there may be some confusion here. To be crystal clear, those folders contain the messages for that account. You cannot delete those folders and expect to retain the messages. But along the lines that David stated, you can, using Windows file explorer, move the directories and files to be under Local Folders. And then in Thunderbird you can remove the Verizon account.