Outlook The Security Certificate Was Issued By A Company You Have Not Chosen To Trust Here

Let’s cut through the noise. This isn't just a random glitch; it’s a critical security mechanism waving a red flag. Here is a deep dive into what causes this error, the genuine risks involved, and the surgical steps to fix it—without compromising your network security. First, understand what Outlook isn’t saying. It is not saying the connection is unencrypted. It is saying, "I have a valid mathematical lock, but I don’t recognize the locksmith who made it."

If you manage Microsoft Outlook in a corporate environment, or even just use it for business email, you have likely stared at that dreaded pop-up: Let’s cut through the noise

Decoding the Outlook Nightmare: "The Security Certificate Was Issued by a Company You Have Not Chosen to Trust" First, understand what Outlook isn’t saying

Never click "Yes" to this error on a public network. Always verify the "Issued by" field. When in doubt, call your IT helpdesk and ask, "Did you guys recently roll out a new internal root CA?" Always verify the "Issued by" field

If the answer is "No," Outlook slams the brakes. This usually happens in three specific scenarios:

Outlook (and Windows) maintains a list of "Trusted Root Certification Authorities." These are global companies like DigiCert, GlobalSign, or Let's Encrypt. When a certificate is presented, Outlook checks: Is the issuer on my trusted list?