IMAP is made for viewing messages from multiple devices. Why did you set up as POP?

Thanks for responding. I use POP because:

1) I've been using it for years and am familiar with how to set up and use it.

2) I do not like getting flooded with waves of email when I fire up my notebook out on the road every several weeks or so. Likewise my phone.

3) I live way off the beaten path and internet to my house is 3G via a Verizon Jetpack which is slow and expensive. I don't want to pay for and wait to download an endless stream of stuff.

4) Power and internet goes out often at my job and so I want to have offline access to my emails.

5) I envision the day when gmail and Google Drive storage will no longer be free and I don't want to have more stuff there than I can bring home.

6) As Google "embraces" and reconfigures IMAP, it's getting harder to stay out of its way.

7) I was hoping to simply leave email on the gmail server and download and store copies on my PC while reading those messages on my phone that I wanted. Didn't work.

So now . . . Suggestions?

re: emails that will not download

Please confirm: Are those emails in the Inbox and not in any other folder on the server? Have you tried logging on to webmail and marking them as unread (assuming they are currently read emails) ?

Thanks for asking:

The "Missing" emails (those which I can see on the server via my web browser, but not on Thunderbird client) are in the Inbox, Important, and All folders. At least a good number of the missing ones are there, I didn't check for every one.

I marked all the the missing ones I found as Unread a couple of days ago. They still don't come up on Thunderbird. For what it's worth, marking them Unread did not cause theym to be read again on my phone.

Re: POP on two different devices and using gmail

Please read all of the information as it suggests you try two processes. One is for regular use and the other is a suggestion if you need to get emails older than 30 days to force a download.

I would suggest this should be used when in general use: Gmail users can use either POP 'normal mode' or 'recent mode' to sync their mail. If you're syncing your mail to one mail client, you should use normal mode. If you're syncing mail to a few different mail clients, then you should use recent mode. Regardless of which behavior you select, any downloaded message will be marked internally as 'popped' and will not be downloaded again.

• https://support.google.com/a/answer/6089246?hl=en

This sounds like once you have used POP on phone, the email is marked as popped by gmail and then cannot be downloaded again to Thunderbird. But gmail have a sort of workaround called 'recent mode'. Recent mode fetches the last 30 days of mail, regardless of whether it's been sent to another POP client already. Info here:

• https://support.google.com/mail/answer/47948

This should get at least the last 30 days and work better for you as you access mail via two pop devices.

However, if you have many emails that are older than 30 days and you really need them on TB, then look at this info, which you could run to get all the pop emails again and then swap back to the 'recent mode' as explained above.

gmail says: Once a message has been 'popped' to your mail client from Gmail, you won't be able to re-download it to any mail client in the future. If for instance, you have to remove and reinstall your mail client from scratch, you won't be able to download previously 'popped' messages unless you select the Enable POP for all mail (even mail that's already been downloaded)

This info is located here:

• https://support.google.com/a/answer/6089246?hl=en

under this heading:

• 'Re-downloading messages and excluding existing messages'

need to scroll down to bottom of page to see it.

Thunderbird also keeps a record of what has been downloaded to prevent it redownloading of same message. The 'popstate.dat' file keeps a record of what has been downloaded. If you delete the popstate.dat file, TB thinks nothing has been downloaded, so after setting gmail to use this: 'Enable POP for all mail (even mail that's already been downloaded)' this will make the pop emails available to be downloaded.

You need to access the Profile folder in TB and delete the popsate.dat file for that pop mail account. The only downside is that you will get (in batches) every email currently in server Inbox after which once downloaded to TB, you would need to sort through deleting duplicates.

The Profile folder is a hidden 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 - this is important
• click on 'Mail' folder
• click on the 'mail account name'
• scroll down and locate and Delete the 'popstate.dat' a DAT File.
• close the window - top right X

Start up 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.

Toad-Hall:

Thanks for all of the information. I think I have this thing fixed but it's been a long and tortuous route to get here. For the sake of others who may follow, I'll summarize the trip.

Your suggestion that gmail will not pop any mail that has already been sent is correct, as is your suggestion to use "recent mode" mode to get around it. It took me a while to learn that the way to turn on "recent mode" is to add the word "recent" to the front of my user name as in "recent:my.user.name@gmail.com" as explained in one of your links.

I did that for both my Thunderbird client and my K-9 app on android.

Then . . . Nuthin'

I eventually found that by adding the prefix to my user name, Thunderbird thought I had changed the user name and it just quit working. It didn't give me any warning, it just didn't do anything when I clicked on [Get All New Messages]. I eventually resolved this by going to (in Thunderbird) File > Get New Messages For > Current Account and checking for new mail. When I checked for mail via THIS route, a box popped up and said that I needed to enter a new password. I entered the old one and voila, it began downloading ALL of my emails for the last 30 days, hundreds of them.

I used (Thunderbird Add-On) Remove Duplicate Messages 0.1.14 and was successful in deleting the duplicates. I've used this add-on before and it's a good one.

Then I added my second gmail account to the K-9 app on my android phone and Google struck back. Gmail refused to accept the account data and sent emails to my primary account saying that I was trying to sign in "from an app that doesn't meet modern security standards." More verbage with dire warnings followed. I followed the links in that email through several web sites and eventually found that I could turn off the nasty little thing by going to google.com on my PC, clicking on the icon with nine little rectangles, selecting My Account > Sign in and Security > Connected Apps and sites > Allow Less Secure Apps and clicking it to ON. The links in the warning email did not give any clear explanation of where to go to turn the nasty thing off.

I'm going to finish rooting my android phone this weekend and get rid of as much of Google as I can. Google has become a purveyor of creepware.

I'm going to wait until Monday to make sure everything's still working and then I'll click the Solved the Problem link.

Thanks again for your wise councel and assistance.

Dave

[Update, 18 April 2016 - Problem still Solved]