If you cannot send nor receive emails then it is possible your Anti-virus/Firewall is blocking Thunderbird program.

Some Antivirus Products also control the Firewall settings eg: Norton.

Close thunderbird. access the AV/Firewall and set Thunderbird to be allowed.

Restart Thunderbird.

Toad Hall, thanks for your suggestion, which was partially successful. I entered an exception for Thunderbird on Windows firewall (strangely, the older, working PC did not require this) and can now send emails, but not receive. I also tried disabling both the firewall and antivirus (Avira) but no dice. The configuration on both machines is identical except that the outgoing server on the working machines is smtp.tpg.com.au, while on the non-working machine it's mail.tpg.com.au. If I change the new machine to smtp, I get a error saying the certificate is not valid. I'm also speaking to the ISP, but if you have any other suggestions (other than investing in some carrier pigeons) I'd be glad to hear them. Thanks again for your help.

As you can now send ok then the outgoing server setting mail.tpg.com.au is correct so you do not need to amend anything to do with smtp settings.

I checked this page: https://www.tpg.com.au/support/generalsetting.php

Can you post the following info so the forum can se your current server settings: In Thunderbird

• Menu icon > Help > Troubleshooting Information
• click on 'copy text to clipboard' button
• In this forum question, right click in a 'Post a Reply' text box and select 'Paste'
• You can edit/remove all info on fonts and printers, but nothing else.

When you startup or click on 'get Messages' what happens? What does it say in the bottom status bar eg: looking up, connecting , connected etc ? Do you get any error message? If yes, what does it say...word for word ?

Hi, Toad Hall, I attach the contents of the Troubleshooting Information page. I spent half an hour on the phone to TPG support yesterday, changing port addresses and re-installing Tbird to no avail. I think they are about to give up on me. The message in the status bar when I Get Messages is as follows:

adsle7hc@tpg.com.au:connected to pop3.tpg.com.au

and on the right hand side,  Unread:0

As I'm sure you realise, adsle7hc is my account name and tonybutton@tpg.com.au is my email alias. So, it looks like it's attaching to the server ok, but finding nothing there. Could there be a disconnect between the account name and email alias ?

Once again, thanks for your help. I appreciate you spending so much time to assist me with this problem. Here's the Troubleshooting info;

 Application Basics

   Name: Thunderbird
   Version: 45.1.1
   User Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.1.1
   Profile Folder: Show Folder

             (Local drive)
   Application Build ID: 20160526140950
   Enabled Plugins: about:plugins
   Build Configuration: about:buildconfig
   Memory Use: about:memory

 Mail and News Accounts
   account1:
     INCOMING: account1, , (pop3) pop3.tpg.com.au:110, alwaysSTARTTLS, passwordCleartext
     OUTGOING: , mail.tpg.com.au:587, alwaysSTARTTLS, passwordCleartext, true

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

 Crash Reports

 Extensions
   Lightning, 4.7.1.1, true, {e2fda1a4-762b-4020-b5ad-a41df1933103}

 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
     dom.apps.reset-permissions: true
     extensions.lastAppVersion: 45.1.1
     font.name.monospace.el: Consolas
     font.name.monospace.x-cyrillic: Consolas
     font.name.monospace.x-unicode: Consolas
     font.name.monospace.x-western: Consolas
     font.name.sans-serif.el: Calibri
     font.name.sans-serif.x-cyrillic: Calibri
     font.name.sans-serif.x-unicode: Calibri
     font.name.sans-serif.x-western: Calibri
     font.name.serif.el: Cambria
     font.name.serif.x-cyrillic: Cambria
     font.name.serif.x-unicode: Cambria
     font.name.serif.x-western: Cambria
     font.size.fixed.el: 14
     font.size.fixed.x-cyrillic: 14
     font.size.fixed.x-unicode: 14
     font.size.fixed.x-western: 14
     font.size.variable.el: 17
     font.size.variable.x-cyrillic: 17
     font.size.variable.x-unicode: 17
     font.size.variable.x-western: 17
     gfx.crash-guard.glcontext.appVersion: 45.1.1
     gfx.crash-guard.glcontext.deviceID: 0x161e
     gfx.crash-guard.glcontext.driverVersion: 20.19.15.4444
     gfx.crash-guard.glcontext.gfx.driver-init.direct3d11-angle: true
     gfx.crash-guard.glcontext.gfx.driver-init.webgl-angle: true
     gfx.crash-guard.glcontext.gfx.driver-init.webgl-angle-force-d3d11: false
     gfx.crash-guard.glcontext.gfx.driver-init.webgl-angle-force-warp: false
     gfx.crash-guard.glcontext.gfx.driver-init.webgl-angle-try-d3d11: true
     gfx.crash-guard.status.glcontext: 2
     mail.openMessageBehavior.version: 1
     mail.winsearch.firstRunDone: true
     mailnews.database.global.datastore.id: 10dd0314-9d08-4efd-b150-48cfe06b197
     network.cookie.prefsMigrated: true
     network.predictor.cleaned-up: true
     places.database.lastMaintenance: 1465180720
     places.history.expiration.transient_current_max_pages: 104858
     plugin.importedState: true
     privacy.donottrackheader.enabled: true

 Graphics

     Adapter Description: Intel(R) HD Graphics 5300
     Vendor ID: 0x8086
     Device ID: 0x161e
     Adapter RAM: Unknown
     Adapter Drivers: igdumdim64 igd10iumd64 igd10iumd64 igd12umd64 igdumdim32 igd10iumd32 igd10iumd32 igd12umd32
     Driver Version: 20.19.15.4444
     Driver Date: 4-22-2016
     Direct2D Enabled: false
     DirectWrite Enabled: false (10.0.10586.0)
     ClearType Parameters: ClearType parameters not found
     WebGL Renderer: Google Inc. -- ANGLE (Intel(R) HD Graphics 5300 Direct3D11 vs_5_0 ps_5_0) -- OpenGL ES 2.0 (ANGLE 2.1.0.316930d51ea9)
     GPU Accelerated Windows: 0

     AzureCanvasBackend: skia
     AzureSkiaAccelerated: 0
     AzureFallbackCanvasBackend: cairo
     AzureContentBackend: cairo

 JavaScript

 Incremental GC: 1

 Accessibility

   Activated: 0
   Prevent Accessibility: 0

 Library Versions

     Expected minimum version
     Version in use

     NSPR
     4.12
     4.12

     NSS
     3.21.1 Basic ECC
     3.21.1 Basic ECC

     NSS Util
     3.21.1
     3.21.1

     NSS SSL
     3.21.1 Basic ECC
     3.21.1 Basic ECC

     NSS S/MIME
     3.21.1 Basic ECC
     3.21.1 Basic ECC

I notice the incoming server settings are using 'pop3.tpg.com.au', but according to the info at the link I mentioned, it should be: mail.tpg.com.au

So, no matter whether using pop, imap for incoming or smtp outgoing, according to the website info the server name should be mail.tpg.com.au

Right click on mail account in Folder Pane and select: Settings clickon 'Server Settings' for the email account

Server name: = mail.tpg.com.au User Name: = full email address click on OK

Restart Thunderbird.

Hi, I've tried both pop3 and mail as the incoming server settings, but it makes no difference. TPG tell me that they are in fact the same. I always get the adsle7hc@tpg.com.au:connected to pop3.tpg.com.au message in the status bar, together with Unread:0, so for some reason Tbird cannot find any messages. TPG have pulled the plug; the Help Desk guy told me he had successfully installed Tbird on a couple of PCs overnight using default values with no problem. Unless you have another idea, I think we may be at the end of the road. I was thinking of trying eMClient or Mailbird Lite to front-end both the TPG and Gmail accounts; what do you think ? Once again, thanks for your time; I've written to Pope Francis recommending your beatification.

I think you are still in the throws of your anti virus. They are not always truthful about being disabled and are prone to blocking things even when they say they are turned off.

I suggest a safe mode boot with networking. To do this you will need a wired connection as I understand the wifi driver do not load in Windows 0 (yay Microsoft) http://www.digitalcitizen.life/4-ways-boot-safe-mode-windows-10

Once you are in safe mode try again to get mail. If it works, uninstall your nti virus program entirely and try to get mail on regular mode. Still working? reinstall the A/V if it stops you at least have a culprit. If it continues to work then all should be good, until next time.

Hi, Matt/Toad Hall, the problem is fixed ! I attached my PC via Ethernet to remove Wifi from the equation and stopped Avira antivirus from loading, but I still couldn't retrieve messages. Following Matt's suggestion, I then actually uninstalled the antivirus and removed the registry entries using CC Cleaner, after which the messages downloaded fine. Of course, it works on Wifi too. Apparently, the mail scanner in Avira can't deal with compressed messages, so it simply ignores them. Avira suggest a config fix to Thunderbird on their website, but it doesn't work. I've raised it with them, but until they fix it, back to AVG. Thanks guys for all your help, I can now enjoy my cool Asus Zenbook !