How EWS retirement affects Sent Items Update (SIU) in CodeTwo Email Signatures 365

Problem:

Microsoft plans to retire Exchange Web Services (EWS) for Exchange Online (Microsoft 365 only) in October 2026. If you use the Sent Items Update (SIU) feature in CodeTwo Email Signatures 365, you might have received the following notification in your Microsoft 365 tenant’s Message center:

Action Required: Update active Exchange Web Services Applications

(...)

In October 2026 we will begin disabling EWS on all M365 tenants worldwide. EWS Applications that have not been migrated will stop functioning.

The following applications on your tenant use EWS:

Entra Application ID

3153c72b-35a8-465b-84d8-dfb56651836a

You want to know if there is anything you need to do to continue using SIU.

Solution:

The AppID mentioned in the message refers to the CodeTwo Email Signatures 365 - Sent Items Update app in your Entra ID. This is a CodeTwo cloud service that uses EWS to update emails in the Sent Items folder with the signature that was added in the cloud (after the email was sent). This service does not affect adding CodeTwo signatures to outgoing emails.

Starting October 2026, Microsoft will begin disabling EWS across all Microsoft 365 (Exchange Online) tenants (in fact, Microsoft has already randomly disabled EWS in some tenants as part of their scream tests). To avoid any disruption in using SIU, we recommend ensuring EWS is forced to be enabled in your tenant until the October 2026 deadline – see how to do this.

How to enable access to EWS

The only method to view and change the current access configuration for EWS is by using PowerShell. Here’s how to do this:

1. Open Windows PowerShell and connect to your Exchange Online organization by following these steps. 
2. Use the following cmdlet to check if EWS is enabled organization-wide:

   Get-OrganizationConfig | select EWSEnabled

   If the result is False or you don’t get any value (Null), as shown in Fig. 1., go to the next step to enable EWS. 

   Important

   The Null value is treated as True until September 2026. Starting October 1, 2026, the Null value for this setting will automatically change to False.

   
   Fig. 1. The cmdlet result showing no (Null) value.

   Note that EWS can be blocked, for instance, as part of Baseline Security Mode (BSM) in the Microsoft 365 admin center (by enabling the Block access to ‎Exchange Web Services setting).

3. To allow EWS for the entire organization, use the following cmdlet (you need to be your organization’s Microsoft 365 Global admin or Exchange admin to be able to do this):

   Set-OrganizationConfig -EwsEnabled:$true

4. When you check the EWS status again, as in step 2, you should get the result shown in Fig. 2.

Fig. 2. Confirmation that EWS is enabled in your Microsoft 365 organization.

Troubleshooting

If you get the following error:

The term 'Set-OrganizationConfig' is not recognized as a name of a cmdlet, function, script file, or executable program.

you need to install and import the Exchange Online PowerShell V3 module using the following cmdlets:

Install-Module -Name ExchangeOnlineManagement;
Import-Module -Name ExchangeOnlineManagement

If you have other problems executing these cmdlets in PowerShell, see the troubleshooting section in this article.