Blog: 2010-02

Fixing Chronic Addressbook Corruption in Thunderbird 2

Is your Thunderbird address book corrupted, and Thunderbird deciding that you want to forget about the thousands of entries in it and start from scratch, and you keep recovering from a backup which works for one run before Thunderbird corrupts it again?

The other day, I ran out of disk space, which led to Thunderbird 2.0.x making a mess. Recovering my email took a while, and then I was stuck in the weird state of Thunderbird repeatedly corrupting the addressbook that I kept restoring from a backup.

Now, if you Google for a solution to "thunderbird corrupt addressbook", you will find lots of advice that people should have kept to themselves. Satisfied that nobody, including Mozilla developers, knows why corruption happens nor how to fix its aftermath, I experimented and quickly found something that worked for me.

The solution for me was (you might not want to try this unless you are a techie who can immediately see the general reason why this works, and don't sue me if you make things worse):

1. Quit Thunderbird.

2. Restore abook.mab from backup.

3. Start Thunderbird.

4. Immediately (trying not to do anything that could modify the addressbook or otherwise barf) export the addressbook to an LDIF tile.

5. Quit Thunderbird.

6. Start Thunderbird. Watch Thunderbird complain that the addressbook is now corrupted again, and let it start with a new one.

7. Import the LDIF file.

8. Quit Thunderbird.

9. Copy the imported .mab file (since the import created a separate addressbook) over abook.mab (which should be very small, since Thunderbird just cheerfully erased your thousands of contacts).

10. Edit the preferences file to remove all the ldap_2. (or whatever) preferences, one of which referenced the import .mab file). You want to be left with only your main addressbook and abook.mab.

11. Start Thunderbird. Admire your restored addressbook.

12. Quit Thunderbird, start it again, admire the lack of message about corrupted addressbook.

(Baseball bat clip art found on Web and of unknown authorship. I hope they don't mind it being used punitively.)

ThinkPad T60 Feedback Noise and Microphone

If your IBM/Lenovo ThinkPad T60 makes a high-pitched squeal when the speaker volume is set near maximum or (oddly enough) when your arm or some other object is placed just so with respect to the T60, then you might have a form of microphone feedback.

The solution (short of fixing the audio hardware and/or drivers) is to mute the mic.

Apparently this is a not-uncommon problem. I thought that the mic might be involved in the strange problem of my T60 making a feedback noise when my forearm, laid in front of the T60, was flexed a certain way. This had happened on two occasions in the last few days. When I Googled for "thinkpad t60 microphone", to make sure that the mic really was where I assumed it to be, the second site hit was "Fixing T60 Microphone Feedback Mute Problem."

I suspect that the root cause of the feedback is bad hardware or driver, and that it was triggered by my arm due to one of: (1) mechanical pressure on mic from the laptop case; (2) acoustic reflection into microphone; (3) bizarre RF interference.