re :I tried restarting with add-ons disabled ,then rebooted back to normal. Nothing changed. I presume you mean you restarted Thunderbird with addons disabled and and then tested to see if the addressing worked, but as nothing worked in safe mode, you restarted in normal mode.

First check settings: Tools > Account Settings > Composition & addressing for the mail account or Menu Icon > Options > Account Settings > Composition & addressing for the mail account

Under 'Addressing' select: 'Use my global LDAP server preferences for this account'

click on 'global Addressing Preferences' button

It will open your Options window on Composition and 'Addressing' tab 'when addressing messages, look for matching entries in: select: 'Local address Books' click on OK

then check address books are selected: 'addressbooks for addresses autocomplete:' click on 'Edit' button make sure all address books you require are selected. then click on OK

Then in Account Settings, check all other mail accounts. when finished click on OK to close and save changes to Account Settings.

Went through all steps as suggested. No change.

In reviewing recent bug fixes, I noted one was applied on 09/24/2014, the same date ass the cited problem popped up. The bug was Bug 974857.

Could this problem be related?

When you click on 'Write' to open a new message. Can you see the 'contacts sidebar' on the left side? If no, View > Select: 'Contacts Sidebar' or toggle view using f9 key confirm you can see the Contacts Sidebar.

Usually, you can select the address book, but can you?

re Bug 974857. This bug relates to anchor links in messages; nothing to do with address book.

DOH! Thanks. Should have known.