outlook.office365.com certificate error

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networkn

Networkn
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#180610 15-Sep-2015 10:34

Had a few calls from customers today complaining they are seeing a warning that:

The security certificate was issued by a company you have not chosen to trust. View the certificate to determine whether you want to trust the certifying authority.

The security certificate has expired or is not yet valid

the name on the the certificate is invalid or does not match the name of the site.

Anyone else seeing this?

Did MS let their certificate expire?

slingynz

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#1387724 15-Sep-2015 10:38

Fine for me.

Cert start 02/15 end 02/16

edit: 16 :|

networkn

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#1387725 15-Sep-2015 10:43

slingynz: Fine for me.

Cert start 02/15 end 02/15

I assume you mean 16, otherwise it's expired already.

CYaBro

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#1387733 15-Sep-2015 11:08

We've got a lot of customers on Office 365, as well as ourselves, and we haven't seen that issue, and haven't heard from any of our customers about it either.
Have you checked their Office 365 Admin portals for any issues listed there by Microsoft?

Opinions are my own and not the views of my employer.

freitasm

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Geekzone

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#1387734 15-Sep-2015 11:09

No problems here.

Are you sure these customers aren't using a proxy or the ISP is running a proxy or perhaps their machines have some fake certs from malware?

Dairyxox

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#1387746 15-Sep-2015 11:14

Working ok here, their system clock isn't out of sync?

wasabi2k

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#1387799 15-Sep-2015 12:33

Click on the padlock/view certificate button in your browser and check the cert subject, date and issuer.

Could be DNS poisoning or something else malware related.

ubergeeknz

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#1387817 15-Sep-2015 12:40

It's possibly DNS hijacking. Check what IP the name resolves to for them, then check it from a known good location. Compare. It should tell you something. Then check their DNS settings are what you expect them to be.