Firefox add-ons woes

I've settled into a comfortable relationship with Firefox—the browser of choice for most tech-minded people. (No slight to Opera and Safari fans out there!) I've even got round to uninstalling Internet Explorer on my XP machine!

Well now, what makes online life good in Firefox, apart from its inherently good qualities, are the plethora of add-ons (user-submitted extensions) that made everything accessible at a single click. Let's see:
1. del.icio.us or Digg made bookmarking a breeze at a single button click,
2. The Session Saver or the Firebug debugger (essential for web developers),
3. Scrapbook allows me to download complete pages (JavaScript and all) to make it available offline for my students,
4. IE-Tab made it possible to request and render pesky websites as Internet Explorer--which I have uninstalled on my machine,
5. DownThemAll! accelerates those huge ISO downloads,
6. Most importantly, the Adblock and NoScript made me feel invincible (almost) surfing on a malware-infested digital jungle.

Now you can imagine my consternation when one day, after one of those automatic Firefox updates (it's now at version 2.0.0.13), none of those beloved add-ons work! Need less to say I felt absolutely naked and vulnerable going to the Internet. I managed to refrain myself from getting online for a couple of hours before I realize I had to do something! Here's the problem:

The extensions are still there, but they're not loaded. When I look at the extensions in the Tools -> Add-ons menu, all of them are marked such:

This add-on will be installed when Firefox is restarted.

And restarting Firefox repeatedly does nothing. A search in Google turned up a post back in July '07 (that's donkey years ago in tech world!!!!), that recommends deleting extensions.cache from the Firefox Application Data folder. Didn't work for me. I was dreading the prospect of having to reinstall Firefox and reinstalling all the extensions.. Another search turns up these posts and they recommended deleting the three extension index files:
extensions.ini
extensions.cache
extensions.rdf
from the folder C:\Documents and Settings\{username}\Application Data\Mozilla\Firefox\Profiles\{profile_salt}\, and restarting Firefox.

VERDICT: Works! I just hope the next time Firefox does auto-update, the extension disappearance and rediscovery won't be part of the routine.