The Bat! Going from POP to IMAP

the bat image OVERVIEW This page is intended to provide detail steps to convert a POP email account in TheBat! to IMAP. The steps may seem tedious, but can be done in little time for most users who have 20 or fewer mail folders. If you have hundreds of mail folders, an option would be to migrate a subset at a time until complete.

PREPARATION: The conversion tool is Thunderbird, as TheBat! does not have this facility, at least not yet. As of this writing, Thunderbird 78 is the default version. Download it here: Thunderbird Download

If you only want Thunderbird for the conversion process, there is a legal portable version supporting both 32 and 64 bit processors that doesn't update the registry at It's the same code, but has a small launcher program. That would allow you to just delete it when finished.

What you must have is the import-export addon.

Prior to proceeding, click each mailbox and folder separately in your POP account in TheBat! and click Tools>Export Messages to>UNIX Mailbox. For example, if you want to move inbox, sentmail, and 5 folders, you would create seven mbox files. NOTE: Be sure to remember their structure (i.e., which folders are subordinate to other folders). Not technically important, but you probably want to reconstruct the folders in IMAP as they were displayed in POP.

  1. Install Thunderbird and set up your email account in IMAP.
  2. Right-click in top area and select 'menu bar' from menu.
  3. Install the addon, by clicking Tools>Addons and select the 'extensions' icon in left sidebar if search window is not visible. Then do search for importexport and install the addon. This generates a restart of Thunderbird.
  4. After installing the addon, you may want to adjust any settings from Tools>Addon Options (generally not needed.)

  1. Position cursor in left sidebar at Local Folders
  2. Right-click and select ImportExportTools>Import mbox file
  3. At that menu, select 'import one or more mbox files...'
  4. This will open a window where you can select all the MBOX files you created during preparation step. All the mbox files will be imported into the Local Folders section, with each folder name appearing with the '.mbox' suffix. If you wish to rename, just press F2 and overtype the displayed folder name.
  5. At this point, all your mail folders are in Thunderbird, along with your email account in IMAP. From here, it is a simple matter of 'drag and drop.' Just select each primary folder and drag over the account name in left sidebar. After dragging all the primary folders, now select and drag any subfolders on top of their parent folder.

COMPLETION: Now that all mail is in Thunderbird, if you desire to stay with Thunderbird, exporting and importing the addressbook is straightforward, as both clients share common options. If you wish to stay with TheBat!, all you need do is remove the POP account and define an IMAP account. Do *NOT* attempt to just overtype the POP account into an IMAP account. I do not recommend retaining the POP account alongside the IMAP account, but that's just my preference - experienced users of TheBat! report no problems with a dual setup.

good luck, david
Updated: October 6, 2020