I assume you're running Thunderbird on Windows. What screen reader are 
you using? Are you using POP or IMAP?

When you say it's taking you longer and longer to reply to messages, 
what do you mean? For example, does it just take longer to return to the 
program once you hit the send button? I don't see how the size of the 
sent folder would impact the performance of sending or replying to messages.

I'd start with David's suggestion. It's a good overall performance 
improvement and may fix this and other issues.

If you do conclude that it's the size of a folder then you can move 
messages from one folder to another within Thunderbird and not have to 
mess with the files on the hard drive. This is what I'd suggest, 
although like I said, I'm not sure your problem is related to how many 
messages you have in a given folder. I'd also want to know if you're 
using POP or IMAP before moving things around since if you're using IMAP 
this will also move the messages around on the server as well.

On 02/23/2015 04:46 PM, David Goldfield wrote:
> Rachel,
> One of the things you might want to consider is compacting the
> mailboxes, which is a bit like running a defrag on your mailboxes. From
> the mailbox you want to compact, you'll find a "compact mailbox" option
> in the file menu; I usually use the keyboard shortcuts of alt-f,
> followed by the letter F. Try doing that first and see if the
> responsiveness improves.
>
> Feel free to visit my Web site
> http://www.davidgoldfield.info
>
>                   David Goldfield,
>          Assistive Technology Specialist
>
> On 2/23/2015 5:26 PM, Rachel wrote:
>> Hi, everyone.
>> I'm using the latest version of Thunderbird and have noticed that over
>> time, it's taking longer and longer for the program to allow me to
>> reply to larger messages.  I'm thinking that the problem may be due to
>> the fact that my Sent and Saved mailboxes are quite large.  Since the
>> program seems to load all mailboxes at once, my thinking is that I
>> could move my current Sent mailbox to a different location on my
>> computer so as to preserve it, which I'd like to do, so that I could
>> start fresh with an empty Sent mailbox.
>>
>> In looking at my profile for, say, the Sent mailbox, I notice there
>> are three files that seem to relate directly to it: one called Sent,
>> one called sent.msf, and one called sent.mozmsgs. From what I can
>> tell, the .mozmsgs file is the one that contains the actual text of
>> the messages belonging to that mailbox.  But what are the other two
>> files?  And if I move my sent.mozmsgs to a different location on my
>> computer, should I also move the Sent file and the sent.msf, too?  And
>> if I move any of these files and restart Thunderbird, will it
>> automatically create a new, empty Sent mailbox?
>> I hope my questions are clear and that I haven't completely confused
>> everyone.
>> Thanks for any help any of you can provide.
>> Rachel
>>
>>
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>
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-- 
Christopher (CJ)
chaltain at Gmail


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