What mail client to choose to work with a large volume of letters (3 mailboxes, POP3, each with more than 16GB of letters)?

Question

Email

Hello, I
have a PC, Outlook 2007 on it, 3 mailboxes (POP3) are connected, I encountered the following problem: a large amount of letters have accumulated on the boxes (each more than 16GB) - Outlook can't cope - constant problems with the database, Google suggested that the problem is in the fact that the max file size is 16GB, when Outlook runs into it - problems begin (Outlook does not automatically split the database into several files).
Cleaning the boxes is not an option - the authorities have no time, and the mail must go.
Switching to IMAP is not offered, only POP.
I tried The Bat - the authorities did not like it.
What are the options? Thunderbird?
PS It takes about 24 hours to pump out one box, there is no time to experiment and install different clients, please tell those who know for sure.
Thanks in advance!

Answer 1

Outlook 2007 - you have not reached the 20 GB limit per box yet. But it starts to fail when the connection is interrupted, one in your 24 hours is enough for the process of receiving mail to start anew, from receiving the entire list of letters (large list) from the server, receiving the headers of the letters, rebuilding the local mailbox file.
Are all 16GB of emails stored on the server? POP3 server? Then you're better off repurposing.

Answer 2

Repurpose to IMAP?
I tried, but it's not very convenient to work - the headers are unloaded, you click on the letter and wait 1-2 seconds until it connects to the server. Very uncomfortable to work.
Are there really no programs that can store a larger volume?
There is a PC nearby, there is one box on it, there was the same problem. Cleaned up, the base became around 9GB. Everything flies (and when the base was 15GB there were no problems) - Athlon X2, a screw with a spindle speed of 5200. This is me because working with 16GB files has not yet brought any convenience.
Regarding the download - if the connection is broken, then it downloads from the letter on which it broke off, I did not see that after that the download would start from the very beginning.
UPDATE:
In this case, how will Outlook store emails? Also as a single file?

Answer 3

16Gb box...POP3...Are you an expert in inventing punishments? Working with even one POP3 box is an unbearable pain, because, well, it is not designed for this! . The protocol is damn old, not designed for the gigantic volumes of current correspondence, operating with one file. One, Carl! This entire box - 16GB - is one file! If a user deletes an old letter that is physically in the middle of the mailbox, the entire mailbox is overwritten! All Carl! Yes, you can pervert a little - install dovecot, enable storage on the server, specify advanced pre-Vecot ones as the box format - but this will not eliminate the need to upload the box to the local computer.
Not a single program can work normally with boxes of such a volume. And here the matter rests not even on the maximum volume of the box, but stupidly on the speed of the screw. Not to mention the fact that the break in the synchronization of the box will lead to the need to download it again
JFYI: My main working box is 8.5G, there really is an archive for 20 years. IMAP. No difficulty in accessing what's in TB, what's in Outlook

Answer 4

POP has been outdated for a very long time. There is also IMAP. In the client settings, there is a checkbox "pump out entire messages" so that not only the headers are downloaded.
Try emClient .