My system cant send the email

can someone explain to me how to interplate this log file.Initially my system was sending emails after work-period closure.Recently the system is not able to send the mail,what could have happened

[General Info]

Application: SambaPOS
Version: 5.2.26
Region: en
DB: SQ
Machine: POSSERVER
User: user
Date: 6/1/2020
Time: 6:23 AM

User Explanation:

user said “”

[Exception Info 1]

Top-level Exception
Type: System.AggregateException
Message: One or more errors occurred.
Source: Samba.Infrastructure
Stack Trace: at Samba.Infrastructure.Helpers.Retry.Do[T](Func`1 action, TimeSpan retryInterval, Int32 retryCount)
at Samba.Infrastructure.Helpers.Retry.Do(Action action, TimeSpan retryInterval, Int32 retryCount)
at Samba.Services.Implementations.EMailService.SendEmail(String smtpServerAddress, String smtpUser, String smtpPassword, Int32 smtpPort, String toEmailAddress, String ccEmailAddresses, String fromEmailAddress, String subject, String body, String fileName, Boolean deleteFile, Boolean bypassSslErrors, Int32 retryCount, Int32 retryMinutes) in C:\Users\vehbi\Source\Repos\sambapos-v5-pro\Samba.Services\Implementations\EMailService.cs:line 36

Inner Exception 1
Type: System.Net.Mail.SmtpException
Message: The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.7.0 Authentication Required. Learn more at
Source: System
Stack Trace: at System.Net.Mail.MailCommand.CheckResponse(SmtpStatusCode statusCode, String response)
at System.Net.Mail.MailCommand.Send(SmtpConnection conn, Byte[] command, MailAddress from, Boolean allowUnicode)
at System.Net.Mail.SmtpTransport.SendMail(MailAddress sender, MailAddressCollection recipients, String deliveryNotify, Boolean allowUnicode, SmtpFailedRecipientException& exception)
at System.Net.Mail.SmtpClient.Send(MailMessage message)
at Samba.Services.Implementations.EMailService.InternalSendEmail(String smtpUser, String smtpPassword, Int32 smtpPort, String toEmailAddress, String ccEmailAddresses, String fromEmailAddress, String subject, String body, String fileName, Boolean bypassSslErrors, MailMessage mail, SmtpClient smtpServer) in C:\Users\vehbi\Source\Repos\sambapos-v5-pro\Samba.Services\Implementations\EMailService.cs:line 77
at Samba.Services.Implementations.EMailService.<>c__DisplayClass2_2.b__0() in C:\Users\vehbi\Source\Repos\sambapos-v5-pro\Samba.Services\Implementations\EMailService.cs:line 36
at Samba.Infrastructure.Helpers.Retry.<>c__DisplayClass0_0.b__0()
at Samba.Infrastructure.Helpers.Retry.Do[T](Func`1 action, TimeSpan retryInterval, Int32 retryCount)


[Assembly Info]

mscorlib, Version=4.0.0.0
PresentationFramework, Version=4.0.0.0
PresentationCore, Version=4.0.0.0
System, Version=4.0.0.0
WindowsBase, Version=4.0.0.0
Samba.Services, Version=1.0.0.0
System.ComponentModel.Composition, Version=4.0.0.0
System.Configuration, Version=4.0.0.0
DevExpress.Xpf.Core.v16.2, Version=16.2.13.0
System.Xaml, Version=4.0.0.0
Microsoft.Practices.Prism.MefExtensions, Version=4.0.0.0
Samba.Presentation.Services, Version=1.0.0.0
Samba.Presentation.Common, Version=1.0.0.0
Samba.Domain, Version=1.0.0.0
Microsoft.Practices.Prism, Version=4.0.0.0
System.Core, Version=4.0.0.0
Samba.Infrastructure, Version=1.0.0.0
DevExpress.Data.v16.2, Version=16.2.13.0
Microsoft.Practices.ServiceLocation, Version=1.0.0.0
Samba.Localization, Version=1.0.0.0
Samba.Persistance, Version=1.0.0.0
FastButton, Version=1.0.0.0


[System Info]

Operating System
-Microsoft Windows 7 Professional
–CodeSet = 1252
–CSDVersion = Service Pack 1
–CurrentTimeZone = 180
–FreePhysicalMemory = 1766208
–OSArchitecture = 32-bit
–OSLanguage = 1033
–ServicePackMajorVersion = 1
–ServicePackMinorVersion = 0
–Version = 6.1.7601

Machine
-POSSERVER
–Manufacturer = Hewlett-Packard
–Model = HP EliteDesk 800 G1 TWR
–TotalPhysicalMemory = 3678781440
–UserName = POSSERVER\user


It is about your mail smtp configration. Maybe changed password.

You changed password, server changed to require auth maybe, hard to say with more info.
Bottom line is smtp auth required.

The email server requires authentication.

Hi sir., how do you authenticity your Gmail beyond allowing less secure apps and enabling imap This is already done

I replied on your other post. Forget imap, thats receiving.
Smtp is what you want.
I have feeling they started to use app specific passwords like many other providers for 3rd party smtp apps.