CodeTwo (Email Signatures 365, Office 365 Migration, Backup): ready for the EWS shutdown?

Short answer: CodeTwo has Graph versions. Email Signatures 365: switch Sent Items Update to its Graph version. Office 365 Migration before 3.3.x and Backup before 2.6.x use EWS: update to the current version.

✔ Has a Microsoft Graph version · vendor statements checked 26 Oct 2026

Deadline: Exchange Online blocks EWS by default from October 2026 (tenants are switched to EwsEnabled False, rollout to late April 2027) and turns it off for good on 1 April 2027, with no exceptions. Exchange Server on-premises is not affected.

Status

Ready after an update or a switch (CodeTwo KB). The first ID is Email Signatures 365, the second an example migration app ID (per-version IDs differ).

App IDs in the EWS usage report:

What to do

  1. Email Signatures 365: in the admin panel switch Sent Items Update to the Graph version.
  2. Migration / Backup: update to 3.3.x / 2.6.x or later.
  3. Then remove the CodeTwo IDs from the allow list and check the usage report a week later.

More than one app? Run the free read-only script: it names every app still calling EWS in your tenant.

Allow-list it safely

Setting EwsAllowedAppIDs replaces the whole list, so adding one ID on its own removes every other app. Read the current list first, then write the merged list:

Get-OrganizationConfig -RetrieveEwsOperationAccessPolicy | Format-List EwsEnabled,EwsAllowedAppIDs
Set-OrganizationConfig -EwsEnabled $true -EwsAllowedAppIDs "<current IDs>,<new ID>"

Changes to the list take up to 24 hours. A blocked call returns HTTP 403 with the header X-EWS-Policy-Reason. The free script prints the merged command for every app in use (it never runs it).

Sources

MSP or IT partner? The M365 Readiness Pack runs this EWS check, the SMTP AUTH check and SPF/DKIM/DMARC for every domain once per client tenant, and writes a client-ready report with your logo, next steps and an email to send the client. Read-only, works with GDAP.

See the pack (from $49)
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