On central admin, you can configure the outgoing email settings at farm level and also you can configure it for a specific web app. But keep in mind, even you configuring it for a specific web app, make sure the farm level settings is configured.
Configure at Farm Level:
Configure the outgoing email setting for SharePoint farm.
1. Verify that the user account that is performing this procedure is a member of the Farm Administrators group on the server that is running the SharePoint Central Administration website.
2. In Central Administration, in the Security section, click Configure Outgoing E-mail Setting sunder the E-Mail and text Messages (SMS).
3. On the Outgoing E-mail Settings page. Please enter the following information.
Outbound SMTP server: type the name of the SMTP server for outgoing email (for example, mail.krossfarm.com)
From address box, type the email address (for example, the site administrator alias) as you want it to be displayed to email recipients.
Reply-to address box, type the email address (for example, a help desk alias) to which you want email recipients to reply.
Use TLS Connection Encryption, Select Yes if you want to enable the encryption for the outgoing emails.
SMTP Server Port, please type the port number on which SMTP configured (for example default is 25).
Character set list, click the character set that is appropriate for your language.
Click OK.
Configure using the PowerShell
let’s configure the same setting using SharePoint PowerShell.
Configure the settings at the farm level.
Launch SharePoint PowerShell console (Run as Administrator)
Run the Below PowerShell, after replacing the values by you
$OutSMTPSvr = ‘ExchangeServer.Amtest.local’
$FromAddr = ‘SharePointSupport-Dev@amtest.local’
$ReplyAddr = ‘SharePointSupport-Dev@amtest.local’
$TLSEncry = $false
$SMTPport = 25
$Charset = 65001
$WebApp = Get-SPWebApplication
$webapp.UpdateMailSettings($OutSMTPSvr,$FromAddr, $ReplyAddr,$Charset, $TLSEncry,$SMTPport)
Configure the settings for a specific web application.
Launch SharePoint PowerShell console (Run as Administrator)
Run the Below PowerShell, after replacing the values by you
$OutSMTPSvr = ‘ExchangeServer.Amtest.local’
$FromAddr = ‘SharePointSupport-Dev@amtest.local’
$ReplyAddr = ‘SharePointSupport-Dev@amtest.local’
$TLSEncry = $false
$SMTPport = 25
$Charset = 65001
$WebApp = Get-SPWebApplication "Http://Url of the web application"
$webapp.UpdateMailSettings($OutSMTPSvr,$FromAddr, $ReplyAddr,$Charset, $TLSEncry,$SMTPport)
Configure The Settings For Central Admin.
Launch SharePoint PowerShell console (Run as Administrator)
Run the Below PowerShell, after replacing the values by you
$OutSMTPSvr = ‘ExchangeServer.Amtest.local’
$FromAddr = ‘SharePointSupport-Dev@amtest.local’
$ReplyAddr = ‘SharePointSupport-Dev@amtest.local’
$TLSEncry = $false
$SMTPport = 25
$Charset = 65001
$WebApp = Get-SPWebApplication -IncludeCentralAdministration | ? { $_.IsAdministrationWebApplication -eq $true }
$webapp.UpdateMailSettings($OutSMTPSvr,$FromAddr, $ReplyAddr,$Charset, $TLSEncry,$SMTPport)