topic Re: SSL Decryption Causing Issues with Office 365 in General Topics

SSL Decryption Causing Issues with Office 365

DJ_1924 — Tue, 27 Oct 2026 16:32:42 GMT

Currently working on a deployment with a few test users utilizing SSL decryption before it's rolled out to a wider user base. Decryption is working for the most part with the required exceptions in place, but having some issues with O365 apps no longer working after it was implemented. I had created an EDL and also explicitly added some Microsoft domains to bypass inspection but the applications still appear to be broken. Wondering what I might have missed in terms of bypassing that traffic.

Re: SSL Decryption Causing Issues with Office 365

BPry — Tue, 27 Oct 2026 17:40:30 GMT

@DJ_1924,

What applications specifically are you running into and are you also possibly using credential-enforcement at all? If you're trying to utilize credential-enforcement that can cause issues if you have categories set to continue, but decryption itself doesn't tend to break O365 applications with the default exceptions in place.

Re: SSL Decryption Causing Issues with Office 365

DJ_1924 — Tue, 27 Oct 2026 19:10:13 GMT

Desktop applications like Outlook and Excel. I'll have to look into credential-enforcement and any possible work arounds if it is enabled.

Re: SSL Decryption Causing Issues with Office 365

DJ_1924 — Tue, 27 Oct 2026 20:30:20 GMT

I have the follow EDL defined https://saasedl.paloaltonetworks.com/feeds/m365/worldwide/any/all/ipv4

Re: SSL Decryption Causing Issues with Office 365

Brandon_Wertz — Wed, 28 Oct 2026 18:31:22 GMT

@DJ_1924 wrote:

I have the follow EDL defined https://saasedl.paloaltonetworks.com/feeds/m365/worldwide/any/all/ipv4

@DJ_1924 -- So you enabled SSL Decrypt, but are using this EDL in a destination no-decrypt rule and user applications are having problems working? Did you look at the specific user traffic/decryption logs and confirmed the user traffic is matching the no-decrypt rule?