Outlook 2016 + Windows 10 + Exchange 2010

[smarties11]

Hi All,

 

I'm having difficulty getting Outlook 2016 to connect to an on-prem Exchange 2010 mailbox with Windows 10.

 

We're looking to deploy Windows 10 soon - I had the same issue months ago on our two IT admin desktops (which are already on Windows 10) and managed to get past it but for some reason this time I can't suss it out! Any ideas?

 

When attempting to connect to a mailbox I'm getting 'Log onto Exchange ActiveSync mail server (EAS): The server cannot be found.'

 

Now I know that Outlook 2016 no longer supports MAPI and EAS is the only option. This should work absolutely fine as we've run EAS for years for mobile devices etc and it still works fine on those. Emails also still work fine on the two IT admin workstations, it's just the initial creation of the e-mail account profile that seems to fail!

 

Things I've done/checked so far....

 

• RPC over HTTP installed on Exchange server (it was)
  
• Autodiscover set up correctly in DNS (it was)
  
• Disabled and re-enabled Outlook Anywhere in Exchange admin
  

 

I've tried disabling proxy in IE incase it was attempting to go through the proxy rather than locally. Doing this makes the error appear immediately (before it would take 20 seconds or so of trying) so I wonder if proxy is some of the issue. It shouldn't be, local exceptions are set for our whole domain and I can access OWA no problem with the proxy not set.

 

Any help gratefully received!

 

Thanks.

[colly72]

Are you using split DNS?

[smarties11]

Nope, we use the same DNS domain internal and external.

[colly72]

I'd think about setting up split DNS, so your internal LAN resolves to your local IP addresses for your exchange server. We set up forward lookup zones for our mail.xxxx.org.uk and autodiscover.xxxx.org.uk so that they resolve to the local exchange server IP address and not out and back in to the public IP. Have you tried the Outlook Connectivity Tester - does this all pass without errors?

 

https://testconnectivity.microsoft.com/

[smarties11]

Sorry, I misunderstood your question! I thought your were asking whether we use a different DNS domain internally to the external one.

 

We do use split DNS. Our internal DNS is set up so that all our web-accessible services are resolved locally on the internal IP.

 

Yes, the MS connectivity tester passes with no errors.

[smarties11]

Update: if I try logged in as the domain administrator account (which is mail enabled) it works perfectly first time. But with any other user it does not...

[colly72]

Is this helpful?

 

Outlook 2016 & Exchange Servers – Graham Walsh | Blog

[smarties11]

Hi, thanks for your reply. Unfortunately that didn't work.

 

However, I have got a bit further this morning. As in my original post, I had already noticed that having a proxy set made a difference to how long it took to come back with an error. With the proxy set, it takes a while, with it unset it is immediate. Playing further with the proxy settings, I've discovered that disabling "detect settings automatically" makes it work. Which is very bizarre?! However, now I know that I've googled Outlook 2016 and 'automatically detect settings' and others have had the same problem. Just need to test this now on a few more machines to make sure it is a reliable fix!

 

So that's great - however what I can't get to work is connecting to a mailbox for another user. So for example, what I am currently trying to achieve is connecting our technician's admin account to her staff account mailbox. Permissions are all set correctly as I have tested in Outlook 2010. It still gives the same error about not being able to find the EAS server....

[k-strider]

you might be able to automate that have a look at this issue... its similar but not quite the same

https://support.microsoft.com/en-sg/help/3119083/outlook-2016-crashes-when-creating-a-new-profile

[smarties11]

Thanks k-strider. Sorry, I should have come back to update, but I was able to automate the unticking of the "automatically detect settings" check box using a registry GPP, following the info in this MSDN article - https://blogs.msdn.microsoft.com/askie/2014/12/17/how-to-use-gpp-registry-to-uncheck-automatically-detect-settings/

 

This worked and I've tested on a few workstations and all is now well as long as the user logged on to the computer is the mailbox owner.

 

However, I still can't get Outlook 2016 to connect to an Exchange 2010 mailbox for a different user when the logged on user has full access rights to the mailbox. Permissions are correct as it works in Outlook 2010. I'm just giving up - there's only one user on site this scenario applies to so I've just moved the mailbox to the account the user is logged on as and that works.