wb0gaz,

I think I'm in the same boat. I put in 10 hr messing with Thunderbird with no success. Do you think I could use EmClient to download my 100K emails and save them on my hard drive. Then delete the oldest 50K from Yahoo but still keep the 100K on my computer? Maybe talk off the forum if you would like. [edited email from public support forum]

Thunderbird or any other email client does not allow synchronizing more than 10,000 Yahoo Mail messages because the restriction is in Yahoo.

To solve this problem, do not use the incoming server imap.mail.yahoo.com, but rather the incoming server export.imap.mail.yahoo.com, and always use port 993. The outgoing port will always be the same: smtp.mail.yahoo.com and its port 465.

Please use Thunderbird using the incoming server export.imap.mail.yahoo.com, and you will synchronize more than 10,000 Yahoo Mail messages.

I hope this helps.

I tested this with a Yahoo account with over 10,000 messages, and using Thunderbird, I managed to sync all the messages via IMAP. I don't know if it's possible for 100,000 or more, but you should try it.

The trick is to change the default incoming Yahoo server, which is imap.mail.yahoo.com, to export.imap.mail.yahoo.com. The port will always be the same: 993. The outgoing port, smtp.mail.yahoo.com, remains unchanged, and its port is 465.

Hice la prueba con una cuenta de yahoo que tengo mas de 10,000 mensajes y usando thunderbird logre que se sincronizaran via imap todos los mensajes que tenia. no se si se puede 100,000 o más pero deberian probar

El truco es cambiar el servidor de entrada por defecto de yahoo que es imap.mail.yahoo.com por este export.imap.mail.yahoo.com y el puerto siempre será el mismo 993 y con el puerto de salida smtp.mail.yahoo.com ese no cambia se mantiene y su puerto 465

Hello Dessing Web, I didn't see any text beyond quote of a post from earlier.

Hello Dstan67, I ended up with Em Client after trying several other (than Thunderbird, after problems there) imap clients. I just stumbled on Em Client in one of a number of searches, but it's where I "landed" given very limited time to wrangle the yahoo email service problems.

I believe Em Client would be a vehicle to try (assuming you are using Windows version that it support). Em Client has a 30-day full function trial period, at that expiration either subscribe yearly for a fee (I wish they just had a perpetual license option, I'd be game for that, as I've found it to be a good tool with a user support community) or register for a free personal license. I've not yet hit that point but will probably just use the free personal license as the fee licenses enable some features that aren't necessary for my use case.

(continued...)

I found that Thunderbird had several issues that weren't compatible with my (abbreviated) learning curve/timeline - I started with Thunderbird in response to Yahoo suddenly changing the free account storage ration from 1 TB to 20 GB. Perhaps some of the problems I encountered when starting with Thunderbird were defects in Yahoo's system, however, I could not resolve.

Yahoo defects and Thunderbird issues (found/worked around once I began working with Em Client:) (1) yahoo had lost/deleted all archived emails prior to mid 2010 (the account goes back some years prior). (2) Thunderbird would not access more than 100000 emails (even though I used export.imap.mail.yahoo.com as the incoming server, (3) it turned out a (very) few emails (with attachments) in the yahoo inbox had "incomplete attachments" (below specific to Em Client handling of these) (4) yahoo had lost the "read/unread" flag attached to emails prior to 2012 - all were set as "read", (5) Thunderbird never did make the yahoo account's online trash folder visible, (6) Yahoo's online webmail service was not able to let me selectively identify groups of Inbox mails (by date range) and then move those to other folders (which was my general intent to bring the account under some control); these attempts ended up with no emails transferred, yet no errors, and of course no recourse for customer support (7) Thunderbird exhibited frequent stability problems (crashes and other somewhat unpredictable results.)

I was surprised that Em Client accessed the ~145000 emails at yahoo (mostly inbox, some other folders), so evidently the 100000 email limit (what Thunderbird displayed when accessing export.mail.imap.yahoo.com) had been solved on the client side by Em Client. This (incomplete view of the Yahoo Inbox) was a serious initial problem in my brief Thunderbird experience.

(quick note) There is an (account) option in Em Client which is optional but says something like "fully download attachments for offline use" - be sure that's selected before proceeding.

In the archiving work I've done so far, some issues are clearly Yahoo's (there's a reason I'd never use anything other than a free yahoo service, and I only am putting this effort into a yahoo email account because I've got a long history with that email account. Otherwise, yecchhhhhhh), and I couldn't determine any useful level of detail on these issues while trying to use Thunderbird due to stability and "completeness" type problems there.

Once on Em Client and Yahoo export.imap.mail.yahoo.com server, I proceeded:

After doing a spot check to see that Em Client was accessing emails going back to the point (mid 2010) prior to which Yahoo had lost all archives, I first created local folders corresponding to the yahoo account folders (mostly Inbox, and a half dozen or so other folders), and copied (not moved) contents of the account folders to the corresponding local folders. This is where I had a few errors (related to individual emails in the Inbox from 2011 and 2012, that problem didn't recur in 2013 or later emails) which was related to the email being deformed in yahoo; once it was apparent that Em Client didn't do anything other than "stop and complain" about these few (maybe a dozen) emails, I repeated the copy (not move) process after deleting the offending email, once the dozen or so were deleted, the copy process completed without further error.

With the malformed emails (about a dozen) removed and all account folder emails copied to corresponding local folders, I then used Em Client "backup" function to generate a single (~18 GB in my case) file which represented the imap view of the online account folders and the new copies in corresponding folders. The backup file format is presumably proprietary to Em Client (I did several and archived them offline). Once that was done, I created a set of folders (using Em Client) in the yahoo account imap view labeled by year (this is for the inbox which was most of the storage) such as Inbox2010, Inbox2011, etc., through Inbox2024. I then used Em Client to identify, select and move (not copy) emails from the account inbox to these (still online) account folders. The next step was to create local copies of Inbox2010, 2011, 2012, etc. as had been done for the original Inbox, etc. Another few Em Client backups were run (the file now larger) and those stored offline.

At this point I've not actually run out of "free" storage on yahoo, but am very close (19.8/20.0 GB), have acceptable back-ups (still requiring Em Client to access the local folders, but that's satisfactory for now.) My going-forward plan is to gradually render the earliest archived year (in my case, Inbox 2010) offline-only to recover some account storage space, and continue this slow migration over time.

Hope this long narrative is useful - please don't rely on it as a "how to" as I've likely included some errors or inconsistencies, but this at least provides a general overview of how I've brought my yahoo email account (somewhat) under control.

Dave