Newly inputted email addresses entered into a new Write message are by default saved in the Collected addreses address book.

Thunderbird does not have a memory or cache of pre entered addresses, it always looks for matches in an address book.

To locate the email address/contact you want to delete: click on 'Address Book' click on 'Collected addresses' select the contact/email address that is wrong and delete or edit and save so that next time you type in a Write message, it offers the correct spelling.

To stop newly entered email addresses from being auto saved to 'Collected Addresses' (or any address book) when you send:

Tools > Options > Composition > Addressing tab or Menu icon > Options > Options > Composition > Addressing tab

uncheck the option : Automatically add outgoing email addresses to my 'Collected Addresses'

(optionally - if you want them saved but in another address book - select another address from the drop down list )

Click on OK

I have this problem too. I have removed incorrect addresses until I'm blue in the face, but they continue to show up in the drop-down list. In case this is helpful -- my email account is through gmail, and I am using an add-on called Google Contacts 0.7.12. I have made sure the erroneous contact addresses are gone from google contacts, through the browser interface.

aparente001: The incorrect invalid, got a typo error etc email addresses are in one of your address books. They may be in more than one address book.

This question has already been marked with a Chosen Solution. Have you read the information in the 'Chosen Solution'?

Have you actually checked to see if you are collecting all your outgoing email address in eg: Collected Addresses address book? Do you have that option to save all your outgoing email address in eg: collected addresses ? Senario: If there is one person, but you managed to enter the email wrongly on more than one occassion, you may discover it is written several variants into that address book.

I checked and double-checked all my address books. The problem is that deleting an address from the Address Book doesn't necessarily get them to disappear from the drop-down.

aparente001: Yes it does. There is no cache or memory. As previously mentioned: Thunderbird does not have a memory or cache of pre entered addresses, it always looks for matches in an address book.

As I said, there is obviously more than one entry.

f you created the Contact and entered the wrong email address or need to update it, in which case it is likely to be in your chosen address book that you use.

If someone sent an email and you had it auto added to an address book, but that person has since changed the email address and you need to locate it, then it may in Personal Address Book.

If you were hand typing in the email addresses and made a few errors, then those could be in the Collected Addresses address book. There is likely to be several variants if you made several errors, so you would be looking for more than one email address.

You still have not stated which address book is selected here: Tools > Options > Composition > Addressing tab or Menu icon > Options > Options > Composition > Addressing tab Is this selected ?  : Automatically add outgoing email addresses to my 'Collected Addresses'

Does it say it uses 'Collected addresses' ? Then if you have been hand typing in the errors then that is where they will be.

One method which may help you locate the bad email address.

open a new Write message select the bad email address in a TO field. Copy the email address part between the < >

Open Address Book Select an address book - suggest you start with Collected addresses paste the bad email address into the top search it will filter on that pasted in email address.

I think I fixed it. I went into the properties for the good address (which was the only one the search was coming up with in any of my address books). There is a field called Additional Email, and that's where the stubborn incorrect address was stored. I deleted it; so far so good.

Thank you for working on this with me.