Migration to Microsoft Graph API for Exchange Online
Changes to Exchange Server
Since customers repeatedly ask how piaX will access future Exchange Server versions, we have summarized the key points below. In particular, we would like to point out the differences between Exchange Online and an on-premises Exchange Server SE.
Exchange Online / 365 (Cloud)
Exchange Online is the cloud-based version of the Exchange Server, usually hosted by Microsoft. This version does not offer complete feature parity with Exchange 2019/SE and has partially limited configuration options. It is continuously developed: new functions are added while others are phased out or disabled.
Exchange Server SE (on-premises)
Exchange SE is the successor to Exchange 2019 for local installation (not cloud-based). The first release (RTM) offers the same feature set as Exchange 2019, but its licensing model has changed to a subscription model. Hence the name “SE” – Subscription Edition. Microsoft refers to this as code-equivalent to Exchange Server SE and Exchange 2019. Further releases are planned for the first half of 2026 (CU1) and the second half of 2026 (CU2), which will bring new Microsoft functionalities.
piaX Interface to Exchange
piaX uses the Exchange Server to exchange and transport data from the ERP system proALPHA to piaX users.
Currently, access to the Exchange Server (both online and on-prem) is handled via the Exchange Web Service (EWS).
It’s XML-based and allows direct access to mailbox data.
Because EWS has existed for many years, Microsoft announced long ago that no further development would take place. Some rarely used functions in Exchange Online have already been restricted or blocked.
The next step will be a complete shutdown of EWS access starting October 1, 2026.
This affects Exchange Online only.
The replacement interface is the Microsoft Graph API.
It doesn’t yet offer the full feature scope of EWS, though most gaps have been closed. The bulk APIs, which are particularly important to us, are currently in public preview.
We are currently extending the piaX interface to include Microsoft Graph API so that future access to Exchange Online will work via Graph.
We expect to provide this interface in the first half of 2026.
For locally installed Exchange Server SE, nothing changes. EWS will continue to be available. Microsoft currently does not plan Graph API support for on-prem Exchange servers.
Summary
Until now, piaX has accessed Exchange Servers via EWS.
In the future, EWS will only be used for on-prem Exchange Server SE.
For Exchange Online (cloud), Graph API must be used by October 1, 2026, at the latest.
Our team will support you through all changes relating to Exchange and piaX.
Please contact us with any questions or support needs.
Your mobileBlox Team
