Do you have the account set in Thunderbird as POP or IMAP?

If set to POP the only folder that syncs with the email providers server is the Inbox. If these messages are in any other folder you will not see them in Thunderbird.

If you want all folders on the providers server to be reflected in Thunderbird re-enter your account as IMAP.

Very much appreciate your reply, thank you. Sorry but I can't fully understand the answer - I have several email addresses in TB and they are all set to POP. In the past I have not had any problem, even from the present contact who does not now come through. Perhaps you could enlighten me further - sorry but I'm still learning!

Since your accounts are POP if the messages are not in your providers inbox Thunderbird will not download them.

But they are in the inbox when i check via the internet - just not downloading in TB. As I said, I can send myself an email and it comes through ok - so why don't the others??

We are not mind readers so can not really guess why email from one individual on ane mail sever account does not download. Have you tried Thunderbird with no add-ons or your operating system safe mode.

To diagnose problems with Thunderbird, try both of the following:

• Restart Thunderbird with add-ons disabled (Thunderbird Safe Mode). On the Help menu, click on "Restart with Add-ons Disabled". If Thunderbird works like normal, there is an Add-on or Theme interfering with normal operations. You will need to re-enable add-ons one at a time until you locate the offender.
• Restart the operating system in safe mode with Networking. This loads only the very basics needed to start your computer while enabling an Internet connection. Click on your operating system for instructions on how to start in safe mode: Windows 8, Windows 7, Windows Vista, Windows XP, OSX

If safe mode for the operating system fixes the issue, there's other software in your computer that's causing problems. Possibilities include but not limited to: AV scanning, virus/malware, background downloads such as program updates.

i appreciate your reply Matt, thanks. Sorry to say that no, it didn't solve the problem. I still cannot receive emails from one contact, despite even adding their addresses to my contact list just in case that was the problem. In the past this contact has come through ok! Emails from others still come through fine. I don't see anything has changed, so I'm still baffled.

have you searched in the box on the toolbar for the mails, just in case they are somewhere else.

What mail provider are your using?

No, there are nowhere else. The provider I am having trouble with is gmail.

I have now got the problem contact to email two emails to me, one to the gmail account which I am having trouble with, and another to a different email address, but both set up in my TB. The latter came through fine, but I'm still not receiving the email into the gmail account. But they appear to be configured exactly the same! Since then I have just received another email (from a different contact) and that too came through fine into gmail. Completely baffling. I've been through the "TB and gmail" Mozilla support page. Anyone got any other ideas?

I think you will find that this contact is being places into the important or other "inbox" by gmail. POP mail downloads the inbox. Nothing else. So if gmail is placing mail from this person into any folder other than inbox then it will not download.

I really appreciate your reply, thankyou. But I'm sorry, I can't make any sense of it. Could you explain further as I'm still completely baffled why this one contact won't download into TB whereas they come through into other email accounts with no problems.

gmail has multiple inboxes... one is called important another I think is called family. These are not named inbox so the mail in them is not downloaded as pop only gets mail from the inbox (and it has to be called inbox) This in not a case of rose by any other name.

Thanks Matt. When I use gmail via the web I find the missing emails fine - and they are in both 'inbox' and 'important'. To reiterate, the problem is these particular emails are not coming through into TB. All my other emails from other contacts come through into my TB gmail ok. Is this contact being blocked somehow? - how to I check this? I just don't understand what else I can do!

Can you supply some info?

When you select the gmail mail account in the folder pane and click on 'GetMail' what happens?

does it say it is looking up, connecting, connected etc?

What error message if any do you get?

Please post this info:

In thunderbird

• Help > Troubleshooting Information
• clickk on 'copy yext to clipboard'
• paste info into this question

you can edit/ remove all info on fonts and printers, but nothing else.

In Tools > Account Settings > Server Settings for the mail account

is this selected:

• Select: check for new messages at startup'
• select 'check for new messages every 10 minutes'
• select 'Automatically download new messages'

If you want to leave messages on the server:

• select 'Leave messages on the server'

• click on ok

When I select gmail account and "get mail", it connects and without any error message. Emails from other than the problem email come through normally. I have the server settings set to "Leave messages on server" but not to check on startup, every 10 mins, or to auto download. I manually check when required. The strange thing is that this contact used to come through ok and is reasonably regular. I have had them send test emails to other accounts that I have and they come through ok, but not into TB. I don't see anything that has changed.

check: Is the email being downloaded, but moved to another folder such as Junk or Deleted, so that you never see the email in the expected folder?

A Filter might be detecting a condition which it can apply to emails from that person. Are there any Message Filters you created that could be filtering emails from that person and performing an action on them, so that you never see the email in the expected folder?

No, the emails are not being downloaded at all - not in any other folder! I don't have any filters on that g-mail account so it's not that. It's just as if, for some reason, that particular contact is being blocked (although not via the web gmail which is where I have to keep checking for their emails!). In the past their emails used to come through into TB ok and I don't see anything has changed. I've even had them send emails to my other accounts to check and they all come through into TB just fine. Completely baffling, - I really appreciate your help with this, thanks!

I have one idea.

The popstate.dat file keeps a record of emails it has downloaded, so that it does not download them again. Usually, if this file has gone awol, you get the same email downloading repeatedly. But I'm wondering if it thinks it has already downloaded the email, although I've not come across this before.

If you deleted the popstate.dat file, Thunderbird would create a new one, but because it is new and empty, it would download everything off the server inbox. This would only happen once and then you would need to remove the duplicate emails.

Prepare Inbox. Suggest you move all current emails in the Inbox to other suitable folders, so the Inbox is empty. Then right click on Inbox and select 'compact'. Then right click on Inbox and select 'Properties' and click on 'Repair folder', click OK.

Then follow instructions to remove the popstate.dat file.

make hidden files visible:

• http://kb.mozillazine.org/Show_hidden_files_and_folders

In Thunderbird

• Help > Troubleshooting Information
• click on 'Show Folder' button
• a new window opens showing your Profile folder

• Close Thunderbird now
• click on 'Mail' folder
• click on the 'mail account name'
• scroll down and locate 'popstate.dat' a DAT File.
• Delete 'popstate.dat'
• close the window - top right X

• Open Thunderbird

Thunderbird will create a new 'popstate.dat' file and start to download everything that is in the server Inbox to the thunderbird mail account Inbox. But only the once.

Remove duplicates and see if those emails were downloaded.

All that sounded like it was worth trying, but unfortunately it had no effect :-( Really sorry to report that after all your assistance, (which is really appreciated). But alas, I had nothing coming into my inbox after doing all that, even though my web mail gmail mailbox still has emails in it. The 'popstate.dat' file is now re-established there though. So I still can't sleep and am nearly bald! Sorry to cause you such a problem!

Really. Add a new account to TB. Make it an IMAP account. Use the recommended settings for Thunderbird.

Stop using POP3. With IMAP, the view on gmail.com will be identical to the view in Thunderbird. It will be impossible for messages of one contact to be invisible.

I hope I did not shock you :)

Add the IMAP account first. If everything works fine, you can remove the POP3 account, after you verified the messages you see in the old account in TB are also visible in the newly added account.