If you are running XP you are also probably using old hardware. The result is not going to be good whatever you do if that is the case.

But the fact is that when Thunderbird is not running, my computer is MUCH more responsive. It's clearly something about the open Thunderbird program. In fact, when I open it, I usually see on the bottom bar that it's reloading all my emails. I'm sure that must be what's slowing everything else down on the computer. Do you mind my asking a related question: I'm wondering why I have 170 GB in my email profile, if I've been using Imap all this time. Shouldn't imap leave all the emails on the Gmail server? (All 3 of my accounts are gmail.)

IMAP stores mail locally to speed access. unless it is disabled in the account settings.

Right click the account, select settings and in Synchronization and Storage set your preferences.

I recall issues with Google account continually updating and reloading in older versions of Thunderbird. What version are you using? (Help menu > About)

Now the slowness is quite possible a side product of your anti virus program. Make sure you have it set to exclude the Thunderbird profile folder from on access type scanning and disable email scanning entirely and see if that has an impact.

Thanks for pointing me to the settings in Synchronizaton and Storage. I had had it set to “Keep messages for this account on this computer.”, so I imagine that’s why it was downloading everything to the local drive?

(If I uncheck that now, but then re-check it again let’s say on Monday, would it synchronize only new emails from Monday forward, or would it also synchronize all the mail that came to me in the interim, between today and Monday?)

I’m running TB version 45.1.0. (I believe that’s the current version?) My antivirus is Avast Free. Per your suggestion, in its "Active Protection - Mail Shield" settings, I just unchecked “Scan inbound mail (Pop3, Imap4)".

Re exclusions, there's a place in Avast’s settings to "Type a path and URLs to be excluded from scanning and from all shield protection," -- but (1) I've no idea what to type there, and (2) it then says, "Be careful when modifying these exclusions as any mistake might put your PC at risk.", so I'm a bit hesitant to enter anything there.

After I unchecked “Scan inbound mail” and then started TB up again, I still saw the rapidly displaying messaging running on the left side of the bottom bar of my Thunderbird screen, and I noticed that it said “Downloading 555 of 1742 messages in Inbox.” (alternating with telling me how much was downloading into other folders). So would that suggest that Avast is not the cause?

This is the extent of my knowledge about avast specifically. https://wiki.mozilla.org/Thunderbird:Testing:Antivirus_Related_Performance_Issues#AVAST

Note here that anti virus programs work on the fear of the ignorant to frighten everyone. What they do not respond well to are directed questions about those generalities.

There is a reason they have exceptions. It is because their defaults mess up many third party programs. For instance it takes an anti virus program about 10 minutes per Gigabyte to scan files. You profile is large and if you look probably has foles that are Gigabyte in size. So if you do not exclude the anti virus madness, your inbox of say 6Gb is scanned every 10 minutes. Oh that's right it takes longer than that to scan it. So in reality it never really gets scanned to the end where the new mails are being added before it starts again.

So the path you need to exclude is your Thunderbird profile path. In Thunderbird on the help menu select troubleshooting information.

In the troubleshooting information is a button to show the profile folder. use it.

The path that is shown by windows explorer is what you need to type into the exclusions on Avast. three of them that path and two repeats one with \mail and another with \imapmail added to them.

https://www.avast.com/faq.php?article=AVKB167#idt_02 Avast offer instructions here. Note that In Exclusions select locations you want to exclude from real-time scanning performed by the File System Shield. This means when weekly or over night scan are done those locations are still checked. just not while you are trying to use the files in them.

Thank you. I hope to have time tomorrow to try the Exclusions part of your suggestions.

BTW, my problem is precisely identical to what this woman described here: https://support.mozilla.org/en-US/questions/1112115 [But there's no record of a resolution provided.]

Could you advise me, once I (hopefully) resolve the problem, is there any way to find out if my 171 GB-sized TB profile is that size due to "artificial" expansion as a result of all the constant downloading? If so, is there a way I can reduce it in size?

Like others with this problem, I do not see any duplicate emails in my folders, but like others, I feel that something is artificially bloating my profile size.

You have mentioned a couple of rather large Inbox files:

"19,000 emails in one Inbox, and 6000 in another"

I appreciate that "Inbox" might be shorthand for "message store", but if your Inbox folders really are that big, I think you might improve matters by reorganizing things.

Personally I think the Inbox is a bad place to keep anything. Mine are kept empty by filing, or immediately deleting unwanted stuff.

However, I think that a few large files are going to cause slower performance than a larger number of smaller files. By filing my messages into topic-related or context-related folders, and archiving annually, I avoid any single folder becoming incrementally very large.

Each folder in Thunderbird is represented by a file in the file system. Keeping your folders small in Thunderbird means you don't have to ask the OS to work with enormous files. If you open a big file, then to access a particular message it has to work through that file and locate that message. Smaller files means less data to shuffle around to get at any specific message. (Possibly the alternative maildir format may work better, as it stores each message in its own file and you don't get these enormous cumulative folder files. But maildir is still an experimental feature and I can't recommend it for general use. And switching to it now wouldn't affect your existing mail store.)

Do you allow Thunderbird to compact? Doing so regularly keeps profile file sizes down to the minimum, by actually removing "deleted" messages. (But if you haven't done this regularly, I'd be hesitant to do it without first making a backup of your profile, as Inbox files appear to tend to become corrupt, and compacting them can lose data. Do a backup, then do a Repair before Compacting.)

Attachments tend to grow larger in email, since they have to be encoded into a text-only format such as Base-64. If you have a lot of attachments and can can detach and save them as files in their own right you may save some disk space and reduce the size of your profile.

Well, that's what works for me. YMMV.

If the constant downloading is growing your profile, compacting will shrink it again.

The issue at https://support.mozilla.org/en-US/questions/1112115 is somewhat different.

Before you spend time on a full out witch hunt and "fixing" things that might not actually help, I suggest you determine to what extent "Thunderbird" alone is the problem.

The big picture questions are 1. describe your hardware in detail - particularly: laptop? how much memory installed? how much disk installed and how much free? 2. describe how much memory thunderbird.exe process is using per taskmgr 3. Start *Windows'* safe mode with networking enabled - XP http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/boot_failsafe.mspx Still In Windows safe mode, start thunderbird in safe mode - https://support.mozilla.org/kb/safe-mode-thunderbird To what extent does performance improve?

I'm going to respond to each of you kind people working to help me, in turn:

Matt:

I can try the Exclusions suggestion you made, but my question to you first is: Is it possible that some other approach (such as deleting the popstate.dat file -- which I saw others say they successfully used ) may work as well, in which case, wouldn't that be preferable to disabling my email AV Mail Shield?

Shouldn't disabling Mail Shield be considered a last resort, since it would put me at increased risk of getting a virus?

Alternatively, if I'm wary of disabling mail shield's presumed protections, would it be better to consider switching to Avira or some other free AV program? (Or do they all interfere with TB?)

> Shouldn't disabling Mail Shield be considered a last resort, since it would put me at increased risk of getting a virus?

Simply stated - no. Some of the info is laid out at https://wiki.mozilla.org/Thunderbird:Testing:Antivirus_Related_Performance_Issues

Zenos:

So first, to clarify what I mean that all my emails are in my Inbox:

In one of my email accounts ("Account A") I have about 50,000 emails in All Mail (just to give you an idea of the total amounts of email in this account). About 18,000 emails are specifically in my Inbox, and then I have about another 15,000 or so emails distributed across about 20 folders. These folders are not subfolders of the Inbox, but rather are, like the Inbox, contained within the imap.googlemail.com folder.

In contrast, In Account B there's only about 6000 emails in the Inbox, but then there's about another 66,000 emails contained in 8 folders which in this care are subfolders of the Inbox.

So when you and others always encourage moving files out of the Inbox into other folders, does it matter whether or not those folders are subfolders within the Inbox, or are separate folders external to it??

A related question I have for you or anyone else: Are the emails contained in All Mail actual duplicates of emails in other folders (and thus taking up duplicate space on my local drive), or is All Mail simply, in reality an index to where the messages are contained in other folders?

I ask this partly because I noticed that Matt, in a post elsewhere, mentioned that he has TB data comprising "over 25 account in hundreds of folders" and yet it only takes up 20 GB.

In contrast, my TB profile, containing 7 years' worth of emails from 3 accounts, takes up a whopping 170 GB on my harddrive.

I'm about to downsize from a 320 GB hard drive to a 256 GB SSD on a new computer, and I can't see how I'll make that work if I truly have 170 GB of email, and want to still be able to access it easily and quickly.

Any suggestions -- for determining if something is artificially making it seem I have a 170 GB profile when perhaps I don't, is also welcome.

BTW, I have tried to compact often in the past 6 months. Sometimes it works, and sometimes not. Today, for example, when I tried to compact, I received the message "The folder [xxxxx] cannot be compacted because another operation is in progress." I suspect that the "operation" referred to is the automatic file "re"-downloading which happens each time I open TB. [Again, that's precisely described here: https://support.mozilla.org/en-US/questions/1112115 ]

Wayne:

Yes, the issue at https://support.mozilla.org/en-US/questions/1112115 is somewhat different than what I'd introduced in this post, however, I also am contending with that issue as well, and am desperately trying to resolve it.

I mention it here partly because I am not sure if the problem of the "rapidly re-downloading of Imap mail each time I open TB" and the problem of an oversized TB profile, and of TB bogging down my machine whenever it's open, might not all be interrelated, or at the very least, exacerbating each other issue.

My hardware: - Dell Inspiron E1505 (6400) laptop running Windows XP (SP3) - 320 GB 7200 RPM HD, of which at moment 46.7 GB are free (out of 296). The free hardspace number ran itself down two months ago to literally MB ("Low disk space" message), and then after I deleted some stuff, but also successfully compacted and unticked "Allow Indexing Service to index this disk for fast file search" in Properties\General on the C drive, I got it to crawl back up to 93 GB free(!). (But since then, the Indexing option trick isn't an option anymore, and day-by-day I see the free GB count falling precipitously. Clearly, something is artificially depleting my drive storage, or at least the stated drive storage.)

- Intel Centrino Core Duo T7200 @ 2.00 Ghz processor - 2 GB DDR2 533 MHz Dimm RAM

Even though it's an old laptop, the truth is that when Thunderbird is closed, it can be very responsive. (I have days where it works just fine, but then other days when, especially if TB is open, everything is slow and constantly hanging and I want to rip out my hair.)

Right now TB says 422,144k under Mem Usage in taskmgr.

Re your last suggestion about Safemode, I'll probably have to wait until a little later today until I have time to review the links you provided and can interrupt my work to shut down. (I do have to shut down and restart to do Safemode, correct?)

Thank you. I will look forward to any further suggestion you and the other "saviors" can provide.

[Besides how desperate this problem of disappearing drive space is making me, I'm hoping to buy a new laptop next week, and I need to figure out quickly if I can manage with a 256 GB SSD, or if I will need, instead, to sacrifice that for a slow 500 to 1 Terabyte Hard Drive, just to accommodate my gargantuan TB profile.]

> the issue at https://support.mozilla.org/en-US/questions/1112115 is somewhat different than what I'd introduced in this post, > I also am contending with that issue as well

Only if Thunderbird disk space being used is greatly more than your actual mail total storage, and you haven't stated that. How much storage does *gmail* web interface say is being used?

> Right now TB says 422,144k under Mem Usage in taskmgr. That's not bad at all.

> - Dell Inspiron E1505 (6400) laptop running Windows XP (SP3) > - 320 GB 7200 RPM HD, of which at moment 46.7 GB are free (out of 296). > - Intel Centrino Core Duo T7200 @ 2.00 Ghz processor > - 2 GB DDR2 533 MHz Dimm RAM > I'm hoping to buy a new laptop next week ... with SSD.

I had a dell d531 with vista, so I totally know what you are dealing with. Now 1.5 years on used Thinkpad W520 150GB SSD. Forget about trying to solve your current Thunderbird perf issues - SSD with a newer laptop will make you perf issues go away, assuming you have appropriate memory - 8+GB for win10. (I've got 20GB)

Don't count on an 255GB disk being enough space: 1. newer Windows OS and all the apps take tons more disk space. 2. unless you manage to cut out another 100GB - which is perhaps is possible.

Whoa! Brilliant! Thank you! I just checked all 3 gmail accounts' storage-in-use reports and, collectively, I only am using ~24 GB! (and I think that may even include some photos stored in one of the gmail accounts).

So that's both truly great and hopeful news, but also then proof that my 170 GB Thunderbird profile is indicative of some serious problem.

Might you have any suggestions of where I should be sleuthing in order to identify why the profile is so large?

Could it be that each time I go into TB it is simply reloading everything again somewhere, so that I am accumulating over time? (Although if that were the case, 24 GB x accessing TB 100s of times would yield way more than 170 GB.)

Actually, I'm using all of 14 GB total for the three accounts! (Found how to check just the Gmail storage.)

So here's a key question:

If I install TB on a new laptop with my 3 accounts set to Imap, and Synchronization and Storage set to "Keep messages for this account on this computer" -- and don't import my TB profile from my old laptop -- will TB just automatically download the 14 GB and that's it?

Could I sort of start fresh that way, free of whatever bloated my profile?

"All Mail" is a gmail quirk. They don't use folders. Everything is lumped into All Mail and messages are tagged. Each tag determines which folder a message appears inside in Thunderbird. If a message has several tags, then that one message appears in several different folders.

Since all the messages you normally need to see have at least one tag and so appear in a folder in Thunderbird, my view is that you don't need to see the All Mail folder in Thunderbird.

You can put subfolders under Inbox, but why? I use an Exchange server which forces me to do this and it seems to me to be illogical to force you to nest all your folders inside another.

> will TB just automatically download the 14 GB and that's it?

It should. And then your 256GB SSD should be plenty big.

Although it would be nice to know why your current machine is downloading too much. Want to ship it to me when you get your new laptop? :)

On your new machine (and even on your current one), in Thunderbird you'll want to unsubscribe the All Mail folder for each account. Then memory usage for each account will drop by about half. See also https://support.mozilla.org/en-US/kb/thunderbird-and-gmail

When TB on my new machine downloads the 14 GB of emails, will it also automatically repopulate TB's left-column folder list with all the same folders as were displaying on my old machine's interface?

And will it then re-sort all my emails into their respective folders?

Or does this require separately importing some type of preferences settings?

(Not clear, if I ship my old machine to you, then what?)

Wayne Mery said

> On your new machine (and even on your current one), in Thunderbird you'll want to unsubscribe the All Mail folder for each account. Then memory usage for each account will drop by about half.

Eureka!

Per your suggestion, I unsubscribed from All Mail in "Account A", and (besides my memory usage decreasing, as shown in taskmanager) my TB profile size plummeted from 171 GB to 127 GB!

Then I unsubscribed from All Mail in "Account B", and my profile size plummeted further to 88 GB.

This is beyond great!

However, what I don't understand is, if All Mail is just an index, and doesn't really hold its own messages, why does it take up space on my local drive?

And secondly, What are other types of folders that are likely contributing to the bloated profile size, and which perhaps I should also unsubscribe from?

(BTW, after the "Account A" All Mail unsubscribe, memory usage did fall by about half, roughly from ~ 400,000k to 225,000k. But after the "Account B" All Mail unsubscribe, memory usage is now showing at about 300,000k. Strange.)