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Users cannot connect to Outlook when windows firewall is enabled on the exchange server

Users cannot connect to Outlook when windows firewall is enabled on the exchange server.  Any ideas how I can set this up so they both work without being at a security risk.  Or should I setup a different firewall for the network.
1 Solution
Hi mkurtzhals,

Disable the windows firewall on the exchange server - software firewalls on windows servers is never a good idea.

Protect yourself at the gateway level, and protect only your workstations with the windows firewall

I agree with redseatechnologies! You shouldn't have the windows firewall on the exchange server. You should have a hardware firewall or a box running a dedicated software firewall at your gateway to the internet! My preference is a Cisco PIX but there are many other firewalls for all budgets large and small.
Turn off the Firewall but If you feel like keepin it on then manually add these ports under the exceptions tab in the Windows Firewall settings.

Port       Process       Description
20     FTP     File Transfer Protocol - Data
21     FTP     File Transfer Protocol - Control
25     SMTP     Simple Mail Transfer Protocol
53     DNS     Domain Name System
69     TFTP     Trivial File Transfer Protocol
80     HTTP     Hypertext Transfer Protocol
110     POP3     Post Office Protocol
443     HTTPS     Hypertext Transfer Protocol - Secure
445                           File Sharing
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If you do that Juan, Outlook will still not connect

You have left out the rpc ports!
Is it possible that the users are not getting an IP address via DHCP?  If so just enable the DHCP client settings so that the users are provided the IP address.  I would also concur and say that the hardware method is the best for firewalls.  You can use PIXs and VPNs to secure your network to best suit your needs.  Cisco is the most used and expensive however.


I would not put a firewall on the exchange server.. have a hardware appliance... however if you want to stick to it, look into enabling RPC over http proxy. this would would work if it is exchange 2003
You can also create a windows firewall rule to allow all IP traffic from your LAN's Network range.  (ie.  But , yes, you really should install a firewall at the gateway.
Except the mainly static ports as above, you should also open DYNAMIC port between Exchange & OUTLOOK connection in firewall. (TCP 1024 - 5000)

SMTP (Simple Mail Transfer Protocol)
This is a protocol for sending e-mail messages between servers. Most e-mail systems that send mail over the Internet use SMTP to send messages from one server to another; the messages can then be retrieved with an e-mail client using either POP or IMAP. In addition, SMTP is generally used to send messages from a mail client to a mail server. This is why you need to specify both the POP or IMAP server and the SMTP server when you configure your e-mail application. (Allow outbound TCP local ports 1024-5000 remote port 25)

More Information
Exchange Server static port mappings

*** Even fixed it in registry
How to configure RPC dynamic port allocation to work with firewalls

I agree that you should disable the windows firewall and protect yourself at gatewat level with a hardware firewall.  I take it that you have already turned off the firewall to check that is the problem.

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