I changed the settings and still get the same error.

There is no point trying arbitrary combinations of server settings. Use the settings required by your email provider. Presumably they do have a support web site with that information available.

The server is still working, as I can use webmail to send emails,

Webmail is irrelevant, it's running on different server(s) than SMTP.

Christ1

Thanks for the suggestion

I did go to the email providers website, and did try their suggested settings.

Still no joy.

It still does not work

What are their suggested settings?

Also, please post your Troubleshooting Information. At the top right of the Thunderbird window, click the menu button , then select Help > Troubleshooting Information. Press the "Copy text to clipboard button" and paste the information into your reply.

Name: Thunderbird

   Version: 102.3.0
   Build ID: 20220914215727
   Distribution ID:
   Update Channel: release
   User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.3.0
   OS: Windows_NT 10.0 19044
   OS Theme:
   Launcher Process: Enabled
   Multiprocess Windows: 0/0
   Fission Windows: 0/0
             Enabled by default
   Remote Processes: 3
   Enterprise Policies: Inactive
   Google Location Service Key: Missing
   Google Safebrowsing Key: Missing
   Mozilla Location Service Key: Missing
   Safe Mode: false
   Memory Size (RAM): 15.9 GB
   Disk Space Available: 705 GB
 Mail and News Accounts
   account1:
     INCOMING: account1, , (none) Local Folders, 0, passwordCleartext
   account4:
     INCOMING: account4, , (imap) mail.optusnet.com.au:143, alwaysSTARTTLS, passwordCleartext
     OUTGOING: , mail.optusnet.com.au:25, alwaysSTARTTLS, passwordCleartext, true
   account6:
     INCOMING: account6, , (imap) mail.optusnet.com.au:143, alwaysSTARTTLS, passwordCleartext
     OUTGOING: , smtp.optusnet.com.au:25, alwaysSTARTTLS, passwordCleartext, true
   account7:
     INCOMING: account7, , (imap) outlook.office365.com:143, alwaysSTARTTLS, passwordCleartext
     OUTGOING: , outlook.office365.com:587, alwaysSTARTTLS, passwordCleartext, true
   account9:
     INCOMING: account9, , (imap) mail.optusnet.com.au:143, alwaysSTARTTLS, passwordCleartext
     OUTGOING: , mail.optusnet.com.au:25, alwaysSTARTTLS, passwordCleartext, true
 Calendar Settings
   Home
     Name
     Value
     Name:
     Type: storage
     Disabled:
     Username:
     URI:
     Refresh Interval:
     Read-only:
     Suppress Alarms:
     Cache Enabled:
     iMIP Identity: id4
     iMIP Disabled:
     iMIP Account:
     Organiser Id:
     Force Email Scheduling:
     Popup Alarms Supported:
     Alarms on Invitation Supported:
     Max Alarms Per Event:
     Attachment Supported:
     Max Categories:
     Privacy State Supported:
     Priority Supported: true
     Event Supported:
     Task Supported:
     Local Time Supported:
     UTC/GMT Supported:
     Auto-Scheduling Supported:
 Crash Reports for the Last 3 Days
 Remote Processes
   Type: Count
     Web Content: 1 / 8
     Extension: 1
     GPU: 1
 Add-ons
     Name
     Type
     Version
     Enabled
     ID
       English (Australian) Dictionary
       dictionary
       2.2.1webext
       true
       en-AU@dictionaries.addons.mozilla.org
       Amazon.co.uk
       extension
       1.1
       true
       amazon@search.mozilla.org
       Bing
       extension
       1.0
       true
       bing@search.mozilla.org
       Chambers (UK)
       extension
       1.0
       true
       chambers-en-GB@search.mozilla.org

       DuckDuckGo
       extension
       1.0
       true
       ddg@search.mozilla.org

       Google
       extension
       1.0
       true
       google@search.mozilla.org

       Manually sort folders
       extension
       2.2.2
       true
       tbsortfolders@xulforum.org

       Wikipedia (en)
       extension
       1.0
       true
       wikipedia@search.mozilla.org

       English (GB) Language Pack
       locale
       102.2.2buildid20220906.224751
       true
       langpack-en-GB@thunderbird.mozilla.org

 Security Software

   Type: Name

     Antivirus: Norton 360
     Antispyware:
     Firewall: Norton 360

Graphics

     Features
     Compositing: WebRender
     Asynchronous Pan/Zoom: wheel input enabled; scrollbar drag enabled; keyboard enabled; autoscroll enabled; smooth pinch-zoom enabled
     WebGL 1 Driver WSI Info: EGL_VENDOR: Google Inc. (Intel)

EGL_VERSION: 1.5 (ANGLE 2.1.15727 git hash: 23851a53779d) EGL_EXTENSIONS: EGL_EXT_create_context_robustness EGL_ANGLE_d3d_share_handle_client_buffer EGL_ANGLE_d3d_texture_client_buffer EGL_ANGLE_surface_d3d_texture_2d_share_handle EGL_ANGLE_query_surface_pointer EGL_ANGLE_window_fixed_size EGL_ANGLE_keyed_mutex EGL_ANGLE_surface_orientation EGL_ANGLE_direct_composition EGL_NV_post_sub_buffer EGL_KHR_create_context EGL_KHR_image EGL_KHR_image_base EGL_KHR_gl_texture_2D_image EGL_KHR_gl_texture_cubemap_image EGL_KHR_gl_renderbuffer_image EGL_KHR_get_all_proc_addresses EGL_KHR_stream EGL_KHR_stream_consumer_gltexture EGL_NV_stream_consumer_gltexture_yuv EGL_ANGLE_flexible_surface_compatibility EGL_ANGLE_stream_producer_d3d_texture EGL_ANGLE_create_context_webgl_compatibility EGL_CHROMIUM_create_context_bind_generates_resource EGL_CHROMIUM_sync_control EGL_EXT_pixel_format_float EGL_KHR_surfaceless_context EGL_ANGLE_display_texture_share_group EGL_ANGLE_display_semaphore_share_group EGL_ANGLE_create_context_client_arrays EGL_ANGLE_program_cache_control EGL_ANGLE_robust_resource_initialization EGL_ANGLE_create_context_extensions_enabled EGL_ANDROID_blob_cache EGL_ANDROID_recordable EGL_ANGLE_image_d3d11_texture EGL_ANGLE_create_context_backwards_compatible EGL_KHR_create_context_no_error EGL_KHR_reusable_sync EGL_EXTENSIONS(nullptr): EGL_EXT_client_extensions EGL_EXT_device_query EGL_EXT_platform_base EGL_EXT_platform_device EGL_ANGLE_platform_angle EGL_ANGLE_platform_angle_d3d EGL_ANGLE_platform_angle_d3d11on12 EGL_ANGLE_device_creation EGL_ANGLE_device_creation_d3d11 EGL_ANGLE_experimental_present_path EGL_KHR_client_get_all_proc_addresses EGL_KHR_debug EGL_ANGLE_explicit_context EGL_ANGLE_feature_control IsWebglOutOfProcessEnabled: 1

     WebGL 1 Driver Renderer: Google Inc. (Intel) -- ANGLE (Intel, Intel(R) HD Graphics Direct3D11 vs_4_1 ps_4_1, D3D11-9.17.10.4459)
     WebGL 1 Driver Version: OpenGL ES 2.0.0 (ANGLE 2.1.15727 git hash: 23851a53779d)
     WebGL 1 Driver Extensions: GL_ANGLE_base_vertex_base_instance GL_ANGLE_client_arrays GL_ANGLE_depth_texture GL_ANGLE_explicit_context GL_ANGLE_explicit_context_gles1 GL_ANGLE_framebuffer_blit GL_ANGLE_framebuffer_multisample GL_ANGLE_get_serialized_context_string GL_ANGLE_get_tex_level_parameter GL_ANGLE_instanced_arrays GL_ANGLE_lossy_etc_decode GL_ANGLE_memory_size GL_ANGLE_multi_draw GL_ANGLE_pack_reverse_row_order GL_ANGLE_program_cache_control GL_ANGLE_provoking_vertex GL_ANGLE_request_extension GL_ANGLE_texture_compression_dxt3 GL_ANGLE_texture_compression_dxt5 GL_ANGLE_texture_usage GL_ANGLE_translated_shader_source GL_CHROMIUM_bind_generates_resource GL_CHROMIUM_bind_uniform_location GL_CHROMIUM_color_buffer_float_rgb GL_CHROMIUM_color_buffer_float_rgba GL_CHROMIUM_copy_compressed_texture GL_CHROMIUM_copy_texture GL_CHROMIUM_lose_context GL_CHROMIUM_sync_query GL_EXT_EGL_image_external_wrap_modes GL_EXT_blend_func_extended GL_EXT_blend_minmax GL_EXT_color_buffer_half_float GL_EXT_debug_label GL_EXT_debug_marker GL_EXT_discard_framebuffer GL_EXT_disjoint_timer_query GL_EXT_draw_buffers GL_EXT_draw_elements_base_vertex GL_EXT_float_blend GL_EXT_frag_depth GL_EXT_instanced_arrays GL_EXT_map_buffer_range GL_EXT_multisampled_render_to_texture GL_EXT_occlusion_query_boolean GL_EXT_read_format_bgra GL_EXT_robustness GL_EXT_sRGB GL_EXT_shader_texture_lod GL_EXT_texture_compression_dxt1 GL_EXT_texture_compression_rgtc GL_EXT_texture_compression_s3tc_srgb GL_EXT_texture_filter_anisotropic GL_EXT_texture_format_BGRA8888 GL_EXT_texture_rg GL_EXT_texture_storage GL_EXT_unpack_subimage GL_KHR_debug GL_KHR_no_error GL_KHR_parallel_shader_compile GL_KHR_robust_buffer_access_behavior GL_NV_EGL_stream_consumer_external GL_NV_fence GL_NV_pack_subimage GL_NV_pixel_buffer_object GL_OES_EGL_image GL_OES_EGL_image_external GL_OES_compressed_EAC_R11_signed_texture GL_OES_compressed_EAC_R11_unsigned_texture GL_OES_compressed_EAC_RG11_signed_texture GL_OES_compressed_EAC_RG11_unsigned_texture GL_OES_compressed_ETC2_RGB8_texture GL_OES_compressed_ETC2_RGBA8_texture GL_OES_compressed_ETC2_punchthroughA_RGBA8_texture GL_OES_compressed_ETC2_punchthroughA_sRGB8_alpha_texture GL_OES_compressed_ETC2_sRGB8_alpha8_texture GL_OES_compressed_ETC2_sRGB8_texture GL_OES_depth24 GL_OES_depth32 GL_OES_draw_elements_base_vertex GL_OES_element_index_uint GL_OES_fbo_render_mipmap GL_OES_get_program_binary GL_OES_mapbuffer GL_OES_packed_depth_stencil GL_OES_rgb8_rgba8 GL_OES_standard_derivatives GL_OES_surfaceless_context GL_OES_texture_border_clamp GL_OES_texture_float GL_OES_texture_float_linear GL_OES_texture_half_float GL_OES_texture_half_float_linear GL_OES_texture_npot GL_OES_texture_stencil8 GL_OES_vertex_array_object GL_WEBGL_video_texture
     WebGL 1 Extensions: ANGLE_instanced_arrays EXT_blend_minmax EXT_color_buffer_half_float EXT_float_blend EXT_frag_depth EXT_shader_texture_lod EXT_sRGB EXT_texture_compression_rgtc EXT_texture_filter_anisotropic MOZ_debug OES_element_index_uint OES_fbo_render_mipmap OES_standard_derivatives OES_texture_float OES_texture_float_linear OES_texture_half_float OES_texture_half_float_linear OES_vertex_array_object WEBGL_color_buffer_float WEBGL_compressed_texture_s3tc WEBGL_compressed_texture_s3tc_srgb WEBGL_debug_renderer_info WEBGL_debug_shaders WEBGL_depth_texture WEBGL_draw_buffers WEBGL_lose_context
     WebGL 2 Driver WSI Info: EGL_VENDOR: Google Inc. (Intel)

EGL_VERSION: 1.5 (ANGLE 2.1.15727 git hash: 23851a53779d) EGL_EXTENSIONS: EGL_EXT_create_context_robustness EGL_ANGLE_d3d_share_handle_client_buffer EGL_ANGLE_d3d_texture_client_buffer EGL_ANGLE_surface_d3d_texture_2d_share_handle EGL_ANGLE_query_surface_pointer EGL_ANGLE_window_fixed_size EGL_ANGLE_keyed_mutex EGL_ANGLE_surface_orientation EGL_ANGLE_direct_composition EGL_NV_post_sub_buffer EGL_KHR_create_context EGL_KHR_image EGL_KHR_image_base EGL_KHR_gl_texture_2D_image EGL_KHR_gl_texture_cubemap_image EGL_KHR_gl_renderbuffer_image EGL_KHR_get_all_proc_addresses EGL_KHR_stream EGL_KHR_stream_consumer_gltexture EGL_NV_stream_consumer_gltexture_yuv EGL_ANGLE_flexible_surface_compatibility EGL_ANGLE_stream_producer_d3d_textur

Here is the suggested set up from Optus Thunderbird Setup Confirm that you're connected to the internet before you begin.

Open Thunderbird From the Main Menu: Go to 'Tools' Select 'Account Settings' From the left hand menu: Click 'Account Actions' Select 'Add Mail Account' Enter the name you'd like to present to email recipient eg. John Citizen Enter your full OptusNet Email Address e.g yourusername@optusnet.com.au Enter your OptusNet Email Address Password Tick 'Remember Your Password' Click 'Continue' Thunderbird will attempt to automatically configure your email, based on the details you've entered. Click 'Stop' to end this process and continue with your OptusNet Email configuration. Click 'Manual Setup' From the left hand pane find the OptusNet details you've just entered: Click the 'Server Settings' option immediately beneath these details From the right hand-side, in the 'Server Name' field: Enter mail.optusnet.com.au In the 'Username Field': Enter your full OptusNet Email address again.- eg. yourusername@optusnet.com.au From the 'Security Settings' options: Select 'None' From the 'Authentication' options: Select 'Normal Password' and enter your OptusNet Email Password if requested. If not an Advanced User. Leave all other settings as given rom the bottom of the left hand pane click on 'Outgoing Server (SMTP)' From the right hand-side: Click 'Add' In the 'Description' field: Enter your full OptusNet Email address again. In the 'Server Name' field: Enter mail.optusnet.com.au From the 'Connection Security' options: Select 'None' From the 'Authentication' options: Select 'Normal Password' and enter your OptusNet Email Password if requested In the 'Username Field': Enter your full OptusNet Email address again.| eg. yourusername@optusnet.com.au Click 'OK' Thunderbird is now configured for use with OptusNet Email. On first use, if Thunderbird asks you for your Email Password again, enter it and tick the option to save the password.

Here is further info Optus provides

There are various email applications for your computer such as Microsoft Outlook, Microsoft Live Mail, Mozilla Thunderbird and Mail for OSX/iOS that you can configure for your OptusNet email account.

These email applications will need to a combination of the following settings, for help with creating a new email account please refer to the Help section within the email application itself.

Your Name: This is the display name for your email account Email address: Your OptusNet email address (eg. <your_username>@optusnet.com.au) Email service: Connect to a POP, IMAP, or HTTP server to send and receive e-mail messages Account Type: POP or POP3 Incoming mail server type: 'POP3' server Incoming mail (POP3): mail.optusnet.com.au Outgoing mail (SMTP): mail.optusnet.com.au Username or Log on ID (if different from e-mail address): The OptusNet username for your OptusNet email account (eg. john_citizen) Password: As provided to you by Optus for your OptusNet email account Log on using: Clear 'text authentication' Remember Password: Ensure this is ticked Require log on using Secure Password Authentication: Ensure this is not ticked

From your Troubleshooting Information:

account4: INCOMING: account4, , (imap) mail.optusnet.com.au:143, alwaysSTARTTLS, passwordCleartext OUTGOING: , mail.optusnet.com.au:25, alwaysSTARTTLS, passwordCleartext, true

From the Optusnet instructions:

In the 'Server Name' field: Enter mail.optusnet.com.au From the 'Connection Security' options: Select 'None'

You've selected 'alwaysSTARTTLS' for 'Connection Security', where you should have selected 'None'. This goes for both, the incoming, and outgoing server.

Note, these settings are inherently insecure. I.e. you're always sending your password to the server in the clear. If Optusnet really don't support any connection security, I'd look for a new email provider. ASAP.

Thanks christ1

I tried those settings but still no luck

Given the woes at Optus this week with their data breach anything is possible. https://www.theguardian.com/australia-news/2022/sep/22/optus-data-breach-who-is-affected-what-has-been-taken-and-what-should-you-do and https://www.afr.com/companies/telecommunications/data-of-9-8m-optus-customers-at-risk-in-worst-case-scenario-20220923-p5bkgc

However, more likely than not if your issue arose immediately post update it is you choice of security software that is at issue.

 Security Software
  Type: Name
    Antivirus: Norton 360
    Antispyware:
    Firewall: Norton 360

This is especially as you are configured to use port 25 to send mail as you are. For most of the last 20 years this port has been used for server to server communications, not mail submission. Norton is almost certain to view anything on that port with suspicion. The modern default is port 465 and while I can find nothing on the optus site saying they have risen from the dark ages of port allocation, I suggest you try it.

I did manage to find a very poor setup for Thunderbird on their site. https://www.optus.com.au/for-you/support/answer?id=1434 which very clearly does not mention changing the default port Thunderbird would choose for SMTP. Port of 465.

I also notice buried in their samsung galaxy information they say the outgoing server to use is smtp.optusnet.com.au despite them says otherwise in the Thunderbird settings. A check of the two server names shows they resolve to the same IP address. Nothing like that to add to confusion. Perhaps security through obscurity. Or just plain old confusion just a red herring either way.

Norton has a very nasty habit of blocking all sorts of things post update, from the internet completely or from accessing certain ports. Standard diagnostics for Norton and their ever helpful mail scanning is to restart your computer in safe mode with networking and see if the issue still occurs without Norton's helpful scanner. (Note using Nortons turn off feature does not work here) Microsoft offer instructions for safe mode with networking here https://support.microsoft.com/en-us/windows/start-your-pc-in-safe-mode-in-windows-92c27cff-db89-8644-1ce4-b3e5e56fe234

Hi Matt Thanks for the great suggestions and ideas. I tried both First changing the setting - did not solve problem Second - started in safe mode - did not solve the problem

I have also tried setting up my Optus email in Outlook (Office 365)

It came up with the same SMTP problem, and could not set up the email.

The fact that two programs/applications (Thunderbird and Outlook) have the same issue, could mean that it is an Optus problem.

I have emailed/contacted Optus to see what their solution is.

Thanks

Steve

I know you don't want to hear it, but the problem is Norton 360. Of that am am almost certain. The more things you try unsuccessfully the more likely it becomes.

Thanks Matt So, what is an solution? Do I have to wait for Norton to do another update? Steve

just try using your system without it for a time. If it works then contact the Norton people and ask them to make it work.

Personally I use windows 10 with only Microsoft defender. I do periodically check using online scanners, but I have not been infected using only Microsoft offering. It does require you to engage brain before fingers. No opening unexpected attachments to email for instance, but that really applies with a paid AV as well.

championss1971 did you have good results?

Hi Wayne

Not yet.

I contacted Norton, and they believe it is an issue with Optus.

I am still waiting for a reply from Optus

Steve

The solution has been found. Optus had blocked Port 25 Solution was to move to a static IP address, where Port 25 had not been blocked Emails are now sending fine