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Thunderbird 2GB inbox splitter Icon

Thunderbird 2GB inbox splitter

Thunderbird 2GB Inbox Splitter, solves full Inbox

3.0 Stars (2)
1 Download (This Week)
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Too much mail in your inbox and Thunderbird has stopped working or has gone nuts? split the Inbox file into multiple files. command-line and GUI, GUI is for Windows 2000/vista/7/8. also added is a merge function via a batch file it calls. read the help first.

This program solves the problem of having a full inbox (or at least staves it off for a while).

the domerge.zip has been made available for those who need only that part.

sf.net is buggy in that it won't let me update my screenshots if the same filename is given the next time. sorry folks, I can't seem to get the folks at sf.net to fix that.

a version of thunderbird is supposed to be coming or is already here that doesn't have the 2GiB/4GiB inbox problem. however, with the testing I have done, it crashes after 32,000 emails due to lack of 32-bit memory. solution: make tb a 64-bit application. request it of Mozilla by commenting on the mozilla google group

Thunderbird 2GB inbox splitter Web Site


  • solves the problem of a 2GB inbox
  • easier to use now: choose number of splits/chunks
  • command-line program and GUI wrapper, so you have access to both if you wish
  • command-line and gui accepts a wide array of number formats as an integer64. integer64 is unsigned and case insensitive. it ignores underscores(_). it can be hexadecimal (start with 0x), decimal (plain number or start with 0d), octal (start with 0, 0q, 0o), binary (start with 0b), and can be appended with SI units (:B :D :DB :H :HB :K :KB :M :MB :G :GB :T :TB :P :PB :E :EB :Z :ZB :Y :YB) or computer units (:Ki :KiB :Mi :MiB :Gi :GiB :Ti :TiB :Pi :PiB :Ei :EiB :Zi :ZiB :Yi :YiB) as a multiplier suffix. priority will be given to longer suffixes in a stream of printable characters. for example 5:k, 20, 0x100, 0b10010011, 0377
  • count time now down to 3 minutes! 60x speed improvement!
  • split time now down to 6 minutes! 60x speed improvement!
  • runs under windows, might run under WINE, DarWINE
  • simple by-the-numbers button interface
  • after split, Thunderbird looks like bunch of folders with all mail in Inbox, however the splits are really there
  • the way the filenames are coded, if you run out of space again, you can split Inbox (or Trash, or Drafts or whatever) again with no problems.
  • Merge previously split files (must point to root split file such as "Inbox") - read help first. this does not run under Wine or DarWINE. requires a CMD shell.I don't know if WINE has that or not. I can try some testing when I get a cdrom drive again.
  • as with anything involving precious data, make a backup first. first rule in computers.
  • support for 64-bit windows with v3.3


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User Ratings

ease 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5 1 / 5
features 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5 1 / 5
design 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5 1 / 5
support 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5 1 / 5
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User Reviews

  • 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5

    WARNING tbmailsplit-3.3-setup.exe and tbmailsplit.zip are infected by Artemis Virus (detected by McAfee) But release 3.2 is clean

    Posted 01/11/2016
  • 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5

    Love it!

    Posted 01/06/2012
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Additional Project Details



Intended Audience

End Users/Desktop

User Interface

Win32 (MS Windows), Command-line

Programming Language

C++, AutoIt



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