Firewall ports for Exchange 2010 for external Outlook access.

We have a single exchange 2010 server installed on a 2008R2 domain controller.
We need to access the server from Outlook 2010 from a PC through the firewall.
Which ports should be open so we can access the server?
We have opened the following ports:
25, 587, 443, 135, 53, 389, 3268, 88.
But it still doesn't work in Outlook 2010 on PC, but it works in Outlook 2012 on Mac.

Do we need to edit the RPC port on CAS using HKLM\SYSTEM\CurrentControlSet\Services\MSExchangeRPC\ParametersSystem\TCP/IP Port ?

Thanks for your help.
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Neil RussellTechnical Development LeadCommented:
Enable outlook anywhere and then you only need ports 80/443 open.

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Pete LongTechnical ConsultantCommented:
Agree, I wrote this a while back it might help

Exchange 2010 - Setup and Deploy Outlook Anywhere

macxpresAuthor Commented:
Sounds great guys, I'll try and respond or close the case, depends on the output.
Thanks again for your quick response.
macxpresAuthor Commented:
It works - thanks again :-)
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