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See Talk:Recovering a missing profile Alice 12:28, 22 August 2007 (UTC)

Corrupt or empty prefs.js

While checking through some bug reports I found the following comment in Bug 205120 - Lost Profile after WIndows Crash

carota 2003-09-05 14:14:07 PDT Comment #12

<snip>

Update #2:

I found my prefs.js content in a recovered file that checkdisk (scandisk?) had put in my C:\FOUND.000 directory. I copied it to my mozilla profile, and all is fine again.

The real question therefore is, how secure is the writing and recovering of prefs.js against random crashes? Could a random crash cause prefs.js to become a "lost chain" that checkdisk might recover and put somewhere else? This is what happened, and this is what caused all the problems.

The fact that the lost fragments of a truncated prefs.js file can be recovered using Chkdsk might be helpful for users who lose their Tbird account settings following a system crash and don't have a prefs.js backup. Chkdsk as a recovery tool was also mentioned in this recent Thunderbird forum thread: Lost Thunderbird settings mails everything...a happy ending. By the way, you can also recover a corrupt bookmarks.html file using Chkdisk - see Lost bookmarks#Other_methods_of_recovery (quote) (Windows) Run the error-checking tool Chkdsk (Windows 2000, XP) or ScanDisk (Windows 95, 98, ME) to see if you can recover any file fragments that contain your lost bookmarks. Look for files with names like FILE0001.chk or FILE0002.chk on the root directory (the files may be inside folders named FOUND.000 or similar). Alice 14:49, 27 August 2007 (UTC)

A google search only found four Thunderbird related threads (one in mozillazine, 2 in a ubuntu forum and one in a german thunderbird forum) that mention prefs.zal and none of them state that the user was able to recover using the contents of that file. I couldn't find any mention of prefs.zal in bugzilla or using the Mozilla cross reference tool. http://forums.mozillazine.org/viewtopic.php?f=39&t=502069 mentioned that prefs.zal had no account information, and was just a copy of the "bad" prefs.js. The workaround was added to the lost profile section - the corrupt or empty prefs.js section deals with corrupted prefs.js files.

I'm going to revert the article to the prior edit, and move the reference to prefs-1.js to the corrupt or empty prefs.js section (fixing a mistake I made a long while ago and didn't realize until just now). If the author of the prefs.zal edit disagrees with my removing their edit please discuss it here, rather than restoring the edit. Tanstaafl 12:46, 13 January 2009 (UTC)