topic Re: Issue with IOS 26 and SMTP in Next-Generation Firewall Discussions

Issue with IOS 26 and SMTP

JuanMAbellan — Mon, 17 Nov 2025 08:02:25 GMT

Hi everyone,

We are experiencing a persistent issue with SMTP sending from iOS devices (specifically 26.1) when SSL Forward Proxy / Decryption is enabled on the firewall(10.2.16-h4).

Is there any bug or limitation published related to this?

Thanks in advance!

Re: Issue with IOS 26 and SMTP

BPry — Mon, 17 Nov 2025 16:00:07 GMT

@JuanMAbellan,

Is this an issue that only started showing up when your devices were updated to 26.1 or is this the first time that you've started trying to decrypt this traffic for iOS devices? Likewise, what application are you talking about and how is it configured? Is this the default Mail app or something like the Outlook app?

Re: Issue with IOS 26 and SMTP

JuanMAbellan — Mon, 17 Nov 2025 16:09:58 GMT

Hello @BPry ,

this happened before. We recently update the firmware due to a bug and see that this issue is still present. Default Mail App.

Regards