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Here is the info. you requested. It's four Cox (not 5) and one g-mail. Also: I have two Win7 Ultimate systems and two Linux systems. I have configured them all to use Thunderbird with the same settings (as far as I know). I want each computer to have the exact same downloaded e-mail. I make sure the setting to leave e-mail on server is set to never delete. This used to work flawlessly on my main two production machines (one a desktop and my laptop). When I checked mail on the laptop while out of town I could come home and download all of those same e-mail to the home pc. It just made me sure I would have a backup. Since I switch systems so frequently I need to be sure I won't miss something important.

are you asleep yet?

here's what you wanted:

Application Basics

   Name: Thunderbird
   Version: 45.5.1
   User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1
   Profile Directory: Open Directory

             (Local drive)
   Application Build ID: 20161130104158
   Enabled Plugins: about:plugins
   Build Configuration: about:buildconfig
   Memory Use: about:memory

 Mail and News Accounts
   account1:
     INCOMING: account1, , (pop3) pop.cox.net:995, SSL, passwordCleartext
     OUTGOING: , smtp.cox.net:465, SSL, passwordCleartext, true

   account2:
     INCOMING: account2, , (none) Local Folders, plain, passwordCleartext

   account3:
     INCOMING: account3, , (pop3) pop.cox.net:995, SSL, passwordCleartext
     OUTGOING: , smtp.cox.net:465, SSL, passwordCleartext, true

   account4:
     INCOMING: account4, , (pop3) pop.cox.net:995, SSL, passwordCleartext
     OUTGOING: , smtp.cox.net:465, SSL, passwordCleartext, true

   account5:
     INCOMING: account5, , (pop3) pop.gmail.com:995, SSL, passwordCleartext
     OUTGOING: , smtp.gmail.com:465, SSL, OAuth2, true

   account6:
     INCOMING: account6, , (pop3) pop.cox.net:995, SSL, passwordCleartext
     OUTGOING: , smtp.cox.net:465, SSL, passwordCleartext, true

 Crash Reports

 Extensions
   CompactHeader, 2.1.0, true, {58D4392A-842E-11DE-B51A-C7B855D89593}
   Lightning, 4.7.4, true, {e2fda1a4-762b-4020-b5ad-a41df1933103}
   Messaging Menu and Unity Launcher integration, 1.3.1, true, [email protected]
   Silvermel and Charamel XT, 2.0.1, true, [email protected]
   Get All Mail Button Thunderbird, 0.1, false, {0D4D76B0-657A-41b0-B3ED-60C638F4D97D}

 Important Modified Preferences

   Name: Value

     browser.cache.disk.capacity: 358400
     browser.cache.disk.filesystem_reported: 1
     browser.cache.disk.smart_size_cached_value: 358400
     browser.cache.disk.smart_size.first_run: false
     browser.cache.disk.smart_size.use_old_max: false
     extensions.lastAppVersion: 45.5.1
     gfx.crash-guard.glcontext.appVersion: 45.5.1
     gfx.crash-guard.glcontext.deviceID: GeForce GT 555M/PCIe/SSE2
     gfx.crash-guard.glcontext.driverVersion: 4.5.0 NVIDIA 367.57
     gfx.crash-guard.status.glcontext: 2
     layers.acceleration.disabled: false
     mail.openMessageBehavior.version: 1
     mailnews.database.global.datastore.id: 63d477ea-ead8-4e70-a1b7-d30fea5925a
     network.cookie.prefsMigrated: true
     network.predictor.cleaned-up: true
     places.database.lastMaintenance: 1481677899
     places.history.expiration.transient_current_max_pages: 104858
     plugin.importedState: true

 Graphics

     Adapter Description: NVIDIA Corporation -- GeForce GT 555M/PCIe/SSE2
     Vendor ID: NVIDIA Corporation
     Device ID: GeForce GT 555M/PCIe/SSE2
     Driver Version: 4.5.0 NVIDIA 367.57
     WebGL Renderer: NVIDIA Corporation -- GeForce GT 555M/PCIe/SSE2 -- 4.5.0 NVIDIA 367.57
     GPU Accelerated Windows: 0

     AzureCanvasBackend: cairo
     AzureSkiaAccelerated: 0
     AzureFallbackCanvasBackend: none
     AzureContentBackend: cairo
     CairoUseXRender: 1

 JavaScript

 Incremental GC: 1

 Accessibility

   Activated: 0
   Prevent Accessibility: 0

 Library Versions

     Expected minimum version
     Version in use

     NSPR
     4.12
     4.12

     NSS
     3.21.3 Basic ECC
     3.21.3 Basic ECC

     NSS Util
     3.21.3
     3.21.3

     NSS SSL
     3.21.3 Basic ECC
     3.21.3 Basic ECC

     NSS S/MIME
     3.21.3 Basic ECC
     3.21.3 Basic ECC

All your accounts are POP. POP only looks at mail in the inbox. my guess is your mail is located in other folders, like gmail important.

Perhaps you need to use IMAP instead to get all your mail displayed.

It's always been POP and all of my mail is still in the "Inbox" on the Cox servers. When I log on to each of the Cox accounts using their Webmail it shows mail that won't download. This DID NOT happen before. I could check my mail from any machine using any interface. I have never had to use imap. One thing I concede is adding g-mail is recent and I can't say anything about it's behavior. I used Outlook 2003 for years on my Windows systems with no sync. issues. When I started using Linux full-time I had to find a compatible e-mail program for all systems. Based on your response, the download behavior is "normal" for Thunderbird. This is totally unacceptable. I can't believe that Outlook did something that Thnderbird can't.

Thank you for your reply. I appreciate your time. I am just disappointed that this can't be fixed.

JB

Lets get this clear. I did not say that it was insurmountable. I said that pop only gets mail from the inbox. That is the case be it Outlook, Thunderbird or Pine.

Does you provider make all old mail available for download and have you set their web site to do so? Google for instance only makes mail available from the day you enable POP unless you specifically change that value. What Cox does I have no idea.

Windows users with your issues about mail not all arriving from the inbox almost always have an anti virus that is delaying the download until it times out. What do you have in your Linux installation with regard to application firewalls, anti virus etc. that might have a similar effect. (delayed communications). Other causes can be bandwidth contention. streaming a movie, downloading another and having someone listening to music for example can saturate even large bandwidths so other application fail to communicate in a timely manner.

Really Outlook has zero relevance in this discussion.

I'll try to be clear. I can log on to Cox web mail and in my "Inbox" for each account is "Mail" It might be 5 or 50 e-mails. When I use my native e-mail client, whether it is on Windows or Linux, those e-mails should download to a local "Inbox" on the individual machine. There is NO anti virus or bandwidth issue. It is a very simple process. Yes Outlook is relevant because it worked as expected and Thunderbird isn't. All I want to know is why. Cox doesn't have any restrictions on how or on what or how many times I check my mail. I pay then to provide it when I want it. There is mail sitting on Cox servers in my "Inbox", Thunderbird just won't download it! Is that clear?

then I suggest you log the connection and find out why.

https://wiki.mozilla.org/MailNews:Logging

Locking. Duplicate posting https://support.mozilla.org/en-US/questions/1151870