Saved logins work, but don't show - window blank and can't show passwords

Question

This has been happening for quite some time now, but I need to resolve it before it can't be. My saved logins work, but when I try to display them I get an empty display. The 'Show Passwords' button is grayed out so no love there.
The dates on my pertinent files:
signons.sqlite 7/23/2010 (looks like it's frozen in time)
signons.sqlite-journal 3/28/2011 (today)
key3.db 3/14/2011
I've tried password exporter add-on and password editor add-on and nothing seems to be able to disply/export my logins and/or passwords. There has to be a trick to get this thing working again. I remember trying to find a fix earlier and it was talking about UTF8 or something on the older signons.txt file.
How do I get my Tools->Options->Security->Saved Passwords
to display my (probably hundreds of) logins and passwords so I can export them for backup ?
TIA, Bill
PS: I do have problems with logins saved since last July that I try to change. It's like it reverts back to the old ones that were saved prior to the FF bug that caused them not to be visible rather than the new ones that I try to save now. Not sure if new logins work right or not, I'm not sure which ones to try that were saved after July (to make a test).

Answer 1

To check whether it's the database being corrupted, I would try deleting the entries that you think are corrupt (after backing up the file of course) to see whether it then shows up in the password manager.
FYI, entries not looking like others doesn't necessarily mean they're corrupt. There are different types of entries, which use different sets of fields. A web form entry uses hostname, formSubmitURL, username, password, usernameField, and passwordField; whereas an HTTP authentication entry uses hostname, httpRealm, username, and password (although in the table username and password become encryptedUsername and encryptedPassword); for other protocols, generally only the hostname, username, and password fields are used.
I hope you can recover your database one way or another. Because of the encryption and the paucity of documentation, it's not easy to retrieve passwords other than through the Password Manager, though I'm sure it's possible. I don't know of any other software that decrypts the database even without a Master Password set, except probably that written for the purpose of stealing passwords, which should never be trusted. If you do find such software and you know it to be trustworthy, let us all know.