Thunderbird/Enterprise/Migration

IMAP Migration Guide (Thunderbird 2 To Thunderbird 3.0)

Warning: This is Draft

This is draft of Migration Guide for corporate users.
Migration Guide is being tried to create, because we knew this kind of documentation is needed in Bug 562589. This draft is a brief summary of knowledge about auto-sync/offline-use settings obtained in the Bug 562589 (as of 2010/05/06).

Backgrounds

Upon release of Thunderbird 3.0, next big changes were made.
- Gloda(Global Search and Indexer) is enabled by default.
- Auto-sync of IMAP folders is enabled by default for all IMAP accounts.
- Per folder "offline use" setting of all IMAP folders is set to "offline use=ON" by default upon migration(first use of Tb 3.0.x).
- View of folder pane is forced to "Smart Folders" even though "All Folders" is Tb 2 user's ordinal choice in his daily use.
- Tb 2's "Account Wizard" and Tb3.0beta's "Account Wizard for Gmail IMAP" is removed before official release of Tb 3.0.0.
But spec of above big changes, required settings for above big changes, are not so well documented yet.

Next configuration is very usual in corporate environment nowadays.
- IMAP is used as corporate standard mail system.
- High mail data volume is held in IMAP folders because of business use.
- Use of Roaming Profile or something similar is not special in corporate environment, because both of roaming and ease of backup/recovery is required in many corporate environment.
It conflicts with Tb 3's "Gloda is enabled by default upon upgrade" and "auto-sync of all IMAP folders is enabled by default upon upgrade" in some places.

Main purpose of mass upgrade from Tb 2 to Tb 3 in corporate environment is never trial and testing of new features. Main puropose of mass upgrade is;
- Tb 2's bug fix
- Improvements in stability
- Improvements in performance
- improvements in usability without breaking existent important features.

This Migration Guide is to avoid unwanted/needless problems which can happen upon upgrade from Tb 2.0.x to Tb 3.0.x if people who has to manage corporate system tried upgrade from Thunderbird 2 to Thunderbird 3 easily.

Disable Migration Assistance

When mass upgrade of many Thunderbird clients in a corporation, dialog for migration option is merely an annoyance for every user.

Disable dialog, please.

lockPref("mailnews.ui.show.migration.on.upgrade",false);

Disable Gloda(Global Search and Indexer)

Gloda is new feature of Thunderbird 3.0 and is enabled by default. Corporate users usually doesn't want very different behaviour from Thunderbird 2. Disable Gloda before migration.

But how? Is it possible? Enhancement is needed?

Disable Auto-sync, Keep per folder "offline use" setting

Auto-sync of IMAP folders is enabled by default for all IMAP accounts. And per folder "offline use" setting of all IMAP folders is set to "offline use=ON" by default upon first use of Tb 3.

Disable auto-sync (one of next two, or both for fail safe)
- lockPref("mail.server.default.autosync_offline_stores", false);
- lockPref("mail.server." + serverFromAccount + ".autosync_offline_stores", false);
Disable per folder "offline use" setting change upon migration
- lockPref("mail.server." + serverFromAccount + ".offline_download", false);

Hints&Tips

mail.server.serverX.offline_download (default=true)
- When an IMAP folder is created or subscribed, set offline use=off if false, set offline use=on if true. i.e. This setting is for default of offline use=on/off of an IMAP folder.
- It's enhanced by bug 562589, and next meaning is added.
  - Upon first use of Tb 3, if serverX.offline_download=false is set before upgrade, IMAP folder's "offline use" is not touched by Migration code of Tb 3.
Current behaviour of UI for auto-sync setting:
- Unchecked->Checked
  1. Set mail.server.serverX.offline_download=true
  2. Set offline use=on of all folders of the IMAP account
- Checked->Unchecked
  1. Set mail.server.serverX.offline_download=false
  2. Set offline use=off of all folders of the IMAP account
Gloda and auto-sync/offline-use are possibly independent, althoug relevant.
- "Download Now" button downloads mail to offline-use regardless of offline-use=On/Off.
- "Download Now" button seems to be intercepted and discarded if auto-sync is enabled and offline-use=On. It looks due to already started schedule based automatic downloading.
- Auto-sync automatically downloads mail data to offline-store if auto-sync is enabled and if offline-use=On is set in an IMAP folder.
- "Work Offline" automatcally downloads mail data to offline-store automatically, if per folder offline-use=On is set in an IMAP folder.
- Gloda indexes mail data in offline-store, if mail data is saved in offline-store, perhaps regardless of auto-sync is enabled/disabled and offline-use=On/Off and Working Online/Working Offline.

"Smart Folders" view at folder pane

View of folder pane is changed to "Smart Folders" by default. As ordinal use is "All Folders", change to "All Folders" should be recommended to users, in order to avoid unwanted questions to Help Center.

Can "forcing Smart Folders view" be stopped? How? Is it possible? Enhancement is needed? Tb 3.1 won't force "Smart Folders" view(or renamed one) upon upgrade?

Account definition by autoconfig

As only "autoconfig" is availabe for account definition, setups for autoconfig should be carefully done, in order to avoid user's confusions due to unexpected behaior of autoconfig or failure during autoconfig, if account definition by user himself is permitted.

IMAP folder file location

Because default of IMAP folder file location is profile directory, big offline-store file produces problem of "too big roaming profile", if Roaming Profile is used. Even if Roaming Profile is not used, performance problem may arise, if profile is located on network resource or if MS Win's Offline File(CSC) is used for the big offline-store file.

In such cases, you need to choose one of next.

When Gloda is mandatory for IMAP mail data
- Locate mail directory for IMAP account at location with which remote/network access won't happen(e.g. "Local Settings" of MS Win)
- Enable auto-sync, and set offline use=on of IMAP folders.
- Accept download of all mails to any PC which uses the IMAP account.
- Accept per PC thread pane column setting of the IMAP accout.
  As thread pane column setting is currently saved in .msf file, and as you selected folder location other than profile directory, data in .msf can not be shared among PCs, even when you use Roaming Profile.
When Gloda is not needed for IMAP mail data
- Locate IMAP folder file at any place you want.
- Disable auto-sync, and/or set offline use=off of all IMAP folders.
  As new feature of "Disk Cache for mail in IMAP folder of offline-use=off" is added to Tb 3, mail data of viewed mail is held in far larger Disk Cache than very small memory cache of Thunderbird 2. So, frequency of problem like "repeatedly downloaded big attachment data" is reduced very much compared to Thunderbird 2.

Online search of IMAP folder

There is next known problem currently.

Online search of Edit/Find/Search Messages is not executed.

Until the bug will be fixed, you need to use Quick Search or Virtual Folder(Saved Search folder) for online search.

Search and "Smart Folders"

If IMAP folder of offline-use=off, full text search by Gloda won't work because of offline-use=off.

And, if not all mails of IMAP folder of offline-use=on is downloaded to offline-store file because of your setting for offline-store file size limitation, Gloda can't find not-downloaded mails.

And, as "Smart Folders" is internally Virtual Folder(Saved Search Folder), a "Smart Folder" can be Virtual Folder of multiple search target folders with mixture of local mail folder, IMAP folder of offline-use=on(all mails are sync'ed), IMAP folder of offline-use=on(not all mails are sync'ed), and IMAP folder of offline-use=off.

Never open bug at bugzilla.mozilla.org for "search can't find my mail" without sufficient checking of "what mail at what kind of folder is not hit by what kind of search", please.