415910 - New account creation because prefs.js disappeared

Status: RESOLVED WORKSFORME

(Core :: Preferences: Backend, defect)

Description

[Laurent Bauvens]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; fr; rv:1.8.1.11) Gecko/20071127 Firefox/2.0.0.11
Build Identifier: Thunderbird 1.5.0.2 (20060308)

We have a strange behaviour of Thunderbird: the file prefs.js disappeared from the user profile and then TB asks user to create a new account.

Generally the file prefs.js don't exist anymore but a prefs-1.js exists.

This behavior seems to be very random but with a great number of stations, the probability of appearance is far from being null.

With Microsoft Process Monitor (http://technet.microsoft.com/en-us/sysinternals/bb896645.aspx), I have seen that TB in a normal situation, before a switch-off, creates a temporary file (prefs.js+1) named prefs-1.js which contains the new user preferences, so it
deletes prefs.js and then renames prefs-1.js with the name prefs.js.

So it seems that thunderbird deletes the prefs.js but don't renames
the new preference file.

Reproducible: Sometimes

Steps to Reproduce:
I did not succeed in reproducing the problem
Actual Results:  
The file prefs.js disappeared from the user profile. A file prefs-1.js is present in the profile.

Expected Results:  
Only one prefs.js in the user profile and no prefs-X.js file.

Comment 1

[Laurent Bauvens]

A search on Google shows me that this issue seems to be recurrent in most versions of Thunderbird and also in Firefox which use the same preference management system. The 1.5.0.2 is our official version deployed over 80.000 seats. So it's impossible to me to report a random issue with a panel of.. one TB 2.0.x.

Comment 2

[Matthias Versen [:Matti]]

a prefs.js loss is happens only for a few people, mostly due to a system crash (Blue Screen).It's possible that a few things changed already between 1.5 and 2.0

Comment 4

[Matthias Versen [:Matti]]

CC David Ascher because this is a hudge userbase with 80k Accounts...

Comment 5

[Laurent Bauvens]

(In reply to comment #3)
> 
> *** This bug has been marked as a duplicate of bug 304045 ***
> 
Hi Matthias

I don't think this bug is a real duplicate of bug 304045 because this last one describes a complete data loss or a corrupted prefs.js file after a crash. TB has then the same reaction with empty profile, corrupted prefs.js or none prefs.js, it runs the wizard to create a new account.

Users who have lost the prefs.js didn't talk about a Windows or a TB crash, but  I admit this is hard to have a witness reliable because the users don't have any particular competence in computer science. So our local support teams report me the prefs.js disappearance.

Comment 6

[Matthias Versen [:Matti]]

There is the problem if Thunderbird, Firefox, Mozilla/Seamonkey crashes itself or if the whole System crashed while the application writes to the prefs.js. We have tons of reports in bugzilla about that. The developers did a few things to avoid this problem and an example is the writing to prefs-1.js and rename it. The timeframe of a possible crash with dataloss is limited but not gone.

It's difficult to fix such things if you don't know how and why this happens.
It could be in your case that the people selected a windows shutdown with an open Thunderbird and the shutdown was too fast.
Do you use NTFS as file system or fat32 ?

But I don't know why Thunderbird doesn't search for the prefs-1.js if the default prefs.js is gone (fix the issue itself).

Comment 7

[Laurent Bauvens]

(In reply to comment #6)
> It's difficult to fix such things if you don't know how and why this happens.
> It could be in your case that the people selected a windows shutdown with an
> open Thunderbird and the shutdown was too fast.
OK, I'm going to advise all our users to always close thunderbird before
shutting down Windows and to ask our local support teams to report if the
amount of disappearances then decreases.

> Do you use NTFS as file system or fat32 ?
FAT32

> But I don't know why Thunderbird doesn't search for the prefs-1.js if the
> default prefs.js is gone (fix the issue itself).
I'm not a software designer. Perhaps it will be a good idea to make a backup
copy and to update the prefs.js more frequently, for example after each option
change from UI and just after autoconfig process. Disk writings need nowadays
only few milliseconds.

Comment 8

[Hermann Schwab]

Is only prefs.js gone, or the mailbox files too?

Comment 9

[Matthias Versen [:Matti]]

only the prefs.js, the mailbox files are usually never lost

Comment 10

[Wayne Mery (:wsmwk)]

not confirmed!    - I only intended to cc:

Comment 11

[Erich Stumptner]

Please have a look at a posting about the concerning to the prefs.js although it's not the way for a solution.

http://portableapps.com/node/11191#comment-77983

Sorry, but I am in the same situation and I have to install an email-client which is able to run for more than 3 weeks without loosing all preferences.

are there any ideas left or it's a bug in the bog?


 

Comment 12

[Laurent Bauvens]

I think an add-on like 'MinimizeToTray' might be a real prefs.js killer because the user doesn't think to stop Thunderbird before shutting down Windows.

With a simple Thunderbird, the risk of a prefs.js loss exists but is low. 
With a Thunderbird MinimizeToTray'ed, I suspect the risk of loss is really increased.

Comment 13

[WADA:World Anti-bad-Duping Agency]

(In reply to comment #6)
> The developers did a few things to avoid this problem and an example is the writing to prefs-1.js and rename it.

The improvement was probably Bug 253259.
Due to frequent loss/corruption of prefs.js in the past, backups.number_of_prefs_copies was introduced by Bug 98476 and multiple copies of prefs-N.js was kept by older versions, in order to make manual recovery by user easier. But the functionality was removed after fix of Bug 253259.
See Bug 246722 Comment #2 for brief history of backups.number_of_prefs_copies.

> The timeframe of a possible crash with dataloss is limited but not gone.

> But I don't know why Thunderbird doesn't search for the prefs-1.js
> if the default prefs.js is gone (fix the issue itself).

Even if "prefs.js update == write prefs-X.js + delete prefs.js + rename prefs-X.js to prefs.js", system crash or power failure while "rename prefs-X.js prefs.js" can cause loss of both. And, prefs-X.js or prefs.js corruption can occur, if power failure occurs before HDD's write-cache is physically written to HDD.
Bring back of backups.number_of_prefs_copies is required?

Comment 15

[Nicholas Nethercote [inactive]]

Since there has been no activity in this bug for 9 years, I am going to be optimistic and assume it's no longer a problem.