RichardMlynka-0539 avatar image
0 Votes"
RichardMlynka-0539 asked RichardMlynka-0539 edited

Unable to send email through OWA when using AD FS pre-authentication


we are unable to send email through OWA published through WAP server 2022 when using AD FS pre-authentication. Also delete of mail does not work.
No problem to read emails.
We use Exchange 2019 CU11.

Everything works when we make following changes (every other setting stays the same):
- we go through WAP 2019
- we change pre-authentication on WAP 2022 to pass-through
- we access internal OWA directly from WAP 2022

Looks like HTTP PUT is not going through when using AD FS pre-authentication on WAP 2022.

Any idea what to try to make WAP 2022 with AD FS pre-authentication for OWA work?

P.S. AD FS on WAP 2022 works for our CRM2016

Thank you,

Kind regards,

· 1
5 |1600 characters needed characters left characters exceeded

Up to 10 attachments (including images) can be used with a maximum of 3.0 MiB each and 30.0 MiB total.


disabling HTTP/2 as default on WAP2022 resolves problem with mail send through OWA/WAP2022.

Disable with this setting:
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\WinHttp]

You can still have Http2Tls enabled:

P.S. Also noted that HTTP/2 on WAP2022 is problem for SPS2019 and MS Edge. Other browsers including IE, Chrome, Firefox have no problem with HTTP/2 on WAP2022


0 Votes 0 ·

0 Answers