How many messages can my Inbox and Sent folders really hold?

Steven-
Glad to hear about your backups (be sure you test a restore once a month or so, too...otherwise backing up is...like....pointless if the restore doesn't work 😉

I am not the Rules Guru, but my guess is that if your rule is looking at 'older than 180 days', it has quite a job ahead of it. Go get a coffee and don't wait for this kettle to boil.

Research SmartFolders.
Reconsider your decision to email yourself a copy of stuff.
Look at smart folders for that.

Look at this thread, near the bottom for some ideas on archiving scripts.
http://discussions.apple.com/thread.jspa?threadID=718313

Good Luck 😉

There is no limit on the number of messages for a mailbox but the recommended mailbox size limit for Tiger Mail is 2 GB.

19K messages in your Inbox - pardon me but WOW!!! and why so many unread messages? Did you not read all these messages or did the Mail.app mark these messages as unread again after being read? I'd be surprised if you have not experienced any problems with this mailbox in all this time.

Since an account's Inbox mailbox is usually the most active mailbox and more prone to corruption over time, it is not a good idea to use an account's Inbox mailbox as the final storage location for all received messages not deleted that you need to keep.

Better to create/utilize "On My Mac" location mailboxes to sort received messages by category and the same with the account's Sent mailbox.

There is a collection of AppleScripts called Mail Scripts you can download at this link.

http://homepage.mac.com/aamann/Mail_Scripts.html

The script to use from the collection of scripts is Archive Messages (Mail) which moves messages from the selected mailbox(es) to an archive mailbox or export them to standard mbox, plain or rich text files for backup purposes or import into other applications. You can select to move all messages or only messages sent within or certain period as well filter messages based on their read and flagged status.

Hi Steve-
I'm not sure about the exact limit you're asking about, but I would advise you to find some kind of archiving answer (?)

1) Any database runs the risk of corruption
2) The bigger the DB, the bigger the risk
3) Unless you're backing up, if your Mail database crashed, you'd be sad.
4) Not that it's my business, but why 4700 unreads? Why not flush those?

I have a client who refuses to purge an Outlook Mailbox with 7500 msgs..and i thought THAT was excessive. (He owns a 3rd generation lighting/home accents business, so he says he needs al these msgs).
Yours makes me nervous.

Someone will have a better idea...but start looking for a disaster plan.

IMO, the best approach is to create custom “On My Mac” mailboxes and organize your mail there however you wish. I, for example, create a folder for each year, and custom mailboxes for different topics within it. You may find the following article useful:

Blue and white Mail folders explained

created a new rule that puts all inbox messages there after they
are more than 180 days old. Waiting for Mail to implement this
rule. It's going very slow but seems to be implementing.

Not sure what you mean, but this doesn’t sound right to me. Mail applies rules automatically to incoming messages only, not to messages already in the Inbox or elsewhere...

(david-y'know...my Thunderbird -PC, not sure if Mac's version is the same - has a rule setting that allows the rules to be run against items already in the inbox...wonder if OP has used/seen something like that.)

wonder if OP has used/seen something like that.

If he has used/seen something like that, it wasn’t in Apple Mail. In Mail you can manually apply rules to any messages you want, and you can trick Mail into automatically apply rules to non-incoming messages by means of AppleScript, but Mail itself applies rules automatically to incoming messages only.

Thanks David...I understand that. And you know? On T-Bird, you also have to manually Run the Rule against items already in the Inbox.

But it looks like he's having some fun, now...now that he ran that 180-day filter against his Inbox.
I'm going to be quiet and watch the master handle the next step. (sshhh. Be vewwy quiet.) 😉

Sure you didn't use a Smart Mailbox for this?

Starting from scratch, Is there any way to archive
the 15,000 or so messages in my Inbox that are older
than 180 days so I can have access to them whenever
I need them?

I provided you a link in my previous post in this thread for a collection of AppleScripts to download called Mail Scripts which includes an Archive Mail script which will perform what you need.

Steven,

Every time you modify a rule, Mail displays the following dialog box:

Apply rules
Do you want to apply your rules to messages in open mailboxes?

Could it be that you clicked Yes while Mail was displaying the contents of the Inbox? That would explain why the rule has been applied to those messages.

Don’t try to fix the problem by deleting anything yet. In the Finder, go to ~/Library/Mail/Mailboxes/. Do you see the newly created mailbox there?