When manual backup does not work as it should be
Backup Text for Whats : Backup Text for WhatsApp allows you to export your WhatsApp messages
WhatCrypt: To decrypt the encrypted WhatsApp Database (crypt 5/7) to unencrypted DB file
Whatsapp Viewer For PC : Display chats from WhatsApp Database
So fiddling around I discovered if your Whatsapp database format is crypt7, you are pretty much left with inaccessible backup if you don't have the key it was created in. The default position for this key would be deep down in System and you have to have Root Access to copy it.
Crypt5 files can still be decoded as the key is pretty much the main gmail account associated with the Android device. The plain db file which is left unencrypted also resides deep in system folder that need root access.
When I was upgrading my phone to Kitkat, it wiped out everything and even though I have two different versions of backup for WhatsApp, the database was not restored after WhatsApp was restored.
Somehow though while trying out several of the apps mentioned, I managed to at least get a copy of readable Whatsapp messages that was missing. For the manual backup, the database for the missing messages were all crypt7 files and my current Android Phone Key would not work with those particular crypt7 files. I had almost forgotten about the other version that was back up using an Backup Application. TO my joy, these are the unencrypted db file and thus was readable on the PC Viewer.
So now I do have a copy of those conversation that I thought would have been lost