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Hello,
I need to show Office365 SMTP certificate in power shell, I was tried below Script but get error.
"s_client -showcerts -starttls smtp -crlf -connect smtp.office365.com:587"
Please help me to do that.
What error do you get? Where did you get this "s_client" script?
Are you trying to run the Openssl application? That has nothing to do with Powershell.
https://www.misterpki.com/openssl-s-client/
I used the Digicert utility to display the cert.
https://www.digicert.com/support/tools/certificate-utility-for-windows
I need to get SMTP certificate from Office 365 portal as an admin to add in SMTP mail service
Below the error message.
s_client: The term 's_client' is not recognized as a name of a cmdlet, function, script file, or executable program.
Check the spelling of the name, or if a path was included, verify that the path is correct and try again.
Like above screen shoot
S_client is a parameter to the openssl program. Try running this.
openssl.exe s_client -showcerts -starttls smtp -crlf -connect smtp.office365.com:587
If you don't have the .exe, then you will need to download it.
https://www.openssl.org/community/binaries.html
https://stackoverflow.com/questions/50625283/how-to-install-openssl-in-windows-10
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I don't think "s_client" is an executable. Isn't it a command (or parameter) that instructs the openssl tool to do something.
Showing up that error .
What can I do to get the certificate?
In what directory have you installed the openssl?
It is in O365 portal, and I want to read it.
No . . . did you install the openssl tools? If you did, in which directory have they been placed?
No I did not.
Then how do expect to run the openssl.exe if it isn't present on your machine???????
What's the correct way to install it?
OPENSSL doesn't provide compiled binaries. They do, however, refer you to a page where 3rd-parties offer compiled binaries for certain operating systems. https://wiki.openssl.org/index.php/Binaries
Instructions for installation should accompany the software you download.
Something about this question just smells wrong. You should not need to use a 3rd party tool like openssl to get connected to O365. For starters, this is not a Poweshell question. So that tag doesn't apply. You should add other relevant forum tags for O365 and Exchange to this question. Next you should explain WHY you need that certificate. How will you use it. What software are you using? Exchange? What version? Explain the big picture of the problem you are trying solve. The O365 forum experts should then be able to help you.
Thank you so much, it's work after installed Openssl.exe.