On Jun 20, 2013, at 9:52 PM, Nobumi Iyanaga <[log in to unmask]> wrote:

> Hello,
> 
> I use Mail.app since OS X began, but it seems to have some grave problems: the Mail folder, in my Library, is becoming huge -- it is now 20.3 GB (20,321,432,464 bytes) with 1,056,521 items in it. In fact, I have only (??) something like 137,173 mails (I got this number using a perl script written by a friend, which counts the number of all the unique message IDs). So there are almost ten times more files than the "real mails" that I have. I think/guess that most of them are duplicated files that were generated by some bug in Mail.app...
> 
> I would like to be able to clean up this mail folder, in a safe way (to not corrupt the mail database...). I found a script set called MailScripts (2.10.3), which seems to contain an AppleScript application, and has a command named "Remove Duplicates", but the web page says that some of the scripts do not work on Lion and later (I am using the newest OS)...
> 
> Has any of you this kind of problems? Has anyone used "Remove Duplicates" command of MailScrips on a Mountain Lion machine? Or would there be any other way to solve this problem?
> 
> I would appreciate any insights.
> 
> Thank you very much in advance.
> 
> Best regard,
> 
> Nobumi Iyanaga
> Tokyo,
> Japan

Greetings,
Sorry I don't know any programs that do this for you. But I'll leave a few Mail management tips--
If you an IMAP user, only keep about 3 months  worth. That should keep your mailbox running fairly smooth.
every year create a folder " on my Mac " or Local to your computer. Copy your files to this folder every so often from your Live IMAP mailbox to your local Folder.

then go through your attachments folders and save files and delete non essentials.

POP users can use the same principal make your incoming pop inbox lighter. less disc read time. Copy old Mail to a NewFolder on my mac. remember to make a new folder each year.

you can find them in ~/Library/Mail and  ~/Library/Mail Downloads

then you can archive and backup your mail.
-j

** I have some scripts that do some handy rsync's