SMTP sending issue CPanel server

Hi I have been using EM-Client for about 4 years but last week decided to load emclient onto a
different / newer PC running windows 7 same as the old PC. At the same time I upgraded from
eM-Client 7 to eMClient 9 and used the backup on old PC and Restore on new PC to transfer all settings and mail messages etc.

Anyway receiving emails via pop 3 on port 110 non secure works just fine.

However SMTP will not send no matter what I try. I found Gary’s note and tried every combination below:

The ports and security policies are specific combinations.
There are the options for SMTP:
Port 587 = Force usage of SSL/TLS
Port 25 = Use SSL/TLS if available
Port 465 = Use SSL/TLS on special port (legacy)

After you have made a change, click on Save & Close, then restart eM Client and try send a message.

You may want to try restarting your router, as that could be the cause.

For others using the Avast/AVG application, disable the Mail Shield and try again.

My host - hostforweb say everything is working on the server they also made test emails on my account and tested via webmail and a email client ( not sure which one ) all works fine on their side.

I get various errors depending on the SMTP settings and will post a log record in a separate post.

Apart from settings incorrect in eM-Client I am wondering if I need to change something on my PC?
I have updated windows firewall to allow em-client, and have also tried stopping the firewall but no success.

Thanks in advance for any help / advice

Here is a error log:

9:20:32 AM [email protected] SMTP Connecting: To [email protected]
9:20:34 AM [email protected] [SMTP] MailClient.Accounts.SocketException: Connection failed due to the following reason:
“Cannot determine the frame size or a corrupted frame was received.”
at MailClient.Protocols.Smtp.SmtpSendCommand.Connect(WorkerStatus status)
at MailClient.Protocols.Smtp.SmtpSendCommand.Execute(WorkerStatus status)
at MailClient.Commands.Command.Process(WorkerStatus status)
EnqueuedStackTrace =
at MailClient.Protocols.Smtp.SmtpAccount.<>c__DisplayClass5_0.b__0()
at MailClient.Protocols.Common.AccountBase.RunIfOnline(Action actionIfOnline, Action actionIfOffline)
at MailClient.Protocols.Smtp.SmtpAccount.SendAsync(IEnumerable1 items, Action1 sentItem, Action`1 completed, CancellationToken cancellationToken)
at MailClient.Accounts.BindingAccountBase.SendInternal()
at MailClient.Accounts.BindingAccountBase.Send()
at MailClient.Accounts.AccountManager.SendAllInternal(Boolean checkIncludeInGlobalOperations)
at MailClient.Accounts.AccountManager.SendAll(Boolean checkIncludeInGlobalOperations)
at MailClient.UI.Forms.formMain.menuItem_SendAll_Click(Object sender, EventArgs e)
at System.Windows.Forms.ToolStripItem.RaiseEvent(Object key, EventArgs e)
at System.Windows.Forms.ToolStripItem.OnClick(EventArgs e)
at System.Windows.Forms.ToolStripMenuItem.OnClick(EventArgs e)
at System.Windows.Forms.ToolStripItem.HandleClick(EventArgs e)
at System.Windows.Forms.ToolStripItem.HandleMouseUp(MouseEventArgs e)
at System.Windows.Forms.ToolStripItem.FireEventInteractive(EventArgs e, ToolStripItemEventType met)
at System.Windows.Forms.ToolStripItem.FireEvent(EventArgs e, ToolStripItemEventType met)
at System.Windows.Forms.ToolStrip.OnMouseUp(MouseEventArgs mea)
at System.Windows.Forms.ToolStripDropDown.OnMouseUp(MouseEventArgs mea)
at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
at System.Windows.Forms.ToolStrip.WndProc(Message& m)
at System.Windows.Forms.ToolStripDropDown.WndProc(Message& m)
at MailClient.Common.UI.Controls.ContextMenuStripEx.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, WM msg, IntPtr wparam, IntPtr lparam)
at Interop.User32.DispatchMessageW(MSG& msg)
at System.Windows.Forms.Application.ComponentManager.Interop.Mso.IMsoComponentManager.FPushMessageLoop(UIntPtr dwComponentID, msoloop uReason, Void* pvLoopData)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(msoloop reason, ApplicationContext context)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(msoloop reason, ApplicationContext context)
at System.Windows.Forms.Application.Run(ApplicationContext context)
at MailClient.Program.<>c.b__187_3()
at System.Windows.Forms.Control.InvokeMarshaledCallbackDo(ThreadMethodEntry tme)
at System.Windows.Forms.Control.InvokeMarshaledCallbackHelper(Object obj)
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Windows.Forms.Control.InvokeMarshaledCallback(ThreadMethodEntry tme)
at System.Windows.Forms.Control.InvokeMarshaledCallbacks()
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
at System.Windows.Forms.ContainerControl.WndProc(Message& m)
at System.Windows.Forms.Form.WndProc(Message& m)
at MailClient.Common.UI.Forms.BaseForm.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, WM msg, IntPtr wparam, IntPtr lparam)
at Xilium.CefGlue.Interop.libcef.run_message_loop()
at MailClient.Program.Main(String[] args)
GUIStatus_Exception_Reported = True

Sounds like you may have possibly some corrupted system OS files and may need to run “SFC” to check.

Also check you only have TLS 1.2 and not 1.3 installed in your OS…

Also check your Net Frameworks are up to date in the OS.

Apart from that eM Client V9 is not really designed for Windows 7. Alot has changed in the OS and eM Client V9 might require newer components that are not in Windows 7.

You should also really be running Windows 10 minimum for security reasons, as Microsoft have not supported Windows 7 for years. Risky running that old OS.

You may need to go back to your older eM Client version if you want to stay on Windows 7.

Thanks for the advice Cyberzork problem solved.

So I ran SFC, and ran a repair on frameworks struggled to work out the TLS 1.2 / 1.3 thing but still failed to get emclient smtp running.

Anyway, I do have a windows 11 machine running a CAD package and decided to load emclient onto that, the installation was very smooth and send / receive works fine on all my email accounts so it seems you were correct Windows 7 was the problem after all.

I wasted hours and hours trying to work around the problem on windows 7.

Thanks for your help cheers keith

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