Up until recently I had all my company email accounts synced to my Windows Phone 8.1 device and PC's. We are using Outlook 2010 and Microsoft Exchange. A few days ago (last Monday to be exact) when I tried to sync my accounts I got the error message attached (error message is the same on both PC and phone).

Does anyone know what it means? Is it something our IT team has to look at? is there a problem with the SSL certificate file being used on Exchange? I tried adding and removing the accounts and it still gives the same error and I spoke to an IT staff member but they didn't know how to solve it.

I also tried manually adding the certificate file to my Windows Phone 8.1 device as .der, .crt and .p7c but each time my phone says this file cannot be opened.  I have not tried fixing it on my PC's.

My work PC, which connects directly to the same Exchange server via Outlook 2013, works fine.

How can I solve this?  Is it a certificate issue?  Is it a network issue (trying to access the Exchange server from outside the office)?. 

The OWA site works fine from the same PC's and phone with this error, except for displaying a message saying the certificate is not trusted, but I just bypass it and get to the login screen.

Many thanks.

Hi Ianwuk,

If the certificate is not trusted then you would see issues as this. As your IT to update the Exchange server with a valid trusted SSL certificate.

Otherwise you can import that certificate to your Trusted Store on the device to avoid such errors.

Hi Ianwuk,

If the certificate is not trusted then you would see issues as this. As your IT to update the Exchange server with a valid trusted SSL certificate.

Otherwise you can import that certificate to your Trusted Store on the device to avoid such e

Thanks for replying.

My company did make some changes (or rather they said that updates were applied) but I don't know what they were.

What is the easiest way to solve this and get my emails back on to my phone?

Many thanks.

Ian

Hi lan,

For your question, we need confirm some points:
1. How about Outlook client works from internal and external?
2. How about OWA works from internal and external?

For client side, please ensure you have update the latest certificate from your CA. You can try below steps for check:
1. Run "MMC" to open Console Root.
2. Click "File" to "Add/Remove Snap-in...", then add Certificates.
3. Switch to "Console Root\Certificates\Trusted Root Certification Authorities\Certificates", then check the certificate which is assigned by your CA.
Note: we can export root certificate to phone client, then install it to troubleshoot your issue.

If not, you can ask your IT administrator to update this certificate or login domain to achieve.

Hello Allen.

Outlook client:

Works fine internally (office)

Doesn't work externally (home).

OWA:
Works fine internally (office)

Inside that location ("Console Root\Certificates\Trusted Root Certification Authorities\Certificates") I have tons of certificates. The only ones though that may be related to my company are missing a friendly name and some are classed as root certificates and some don't say anything at all.

See the image below (mail server name crossed out).

What can I do now?

Many thanks.

• Edited by ianwuk 16 minutes ago