setting proxy authentication information in microsoft outllook



I need to have select my proxy from
internet options / connections / LAN Settings to access web sites as a
result of using an ISA Server in my company and it requires authentication

Task 'Hotmail: Downloading folder list. ' reported error (0x800CCC37) :
'Your proxy requires you to authenticate. Contact your network administrator
for assistance.The server responded 'Proxy Authentication Required ( The ISA
Server requires authorization to fulfill the request. Access to the Web
Proxy service is denied. )'. '

If i disconfigure this settings from internet options.

Task 'Hotmail: Downloading folder list. ' reported error (0x800CCC33) :
'Access to the account was denied. Verify that your username and password
are correct.The server responded 'Forbidden ( The ISA Server denies the
specified Uniform Resource Locator (URL). )'. '

Is there any way to set a proxy server for http mail servers in microsoft
outlook ????? (using registry etc.)

Terry Liu [MSFT]

Please refer to this Knowledge Base article:

287921 ISA Server Configuration Options for Hotmail Access When You Use

BTW: Thank you, Andrew, for your contribution in this newsgroup.

Have a nice day!

Best regards,

Terry Liu
Microsoft Online Support Engineer

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Jun 2, 2009
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Setting up if NOT Admin of ISA / Domain

I have a query regarding the steps provided by Microsoft in the linked KB.

If you are not a domain admin, nor do you have administrative access to the ISA server, and your company will not agree to reconfiguring ISA as per the steps provided in the KB, is there any other way Outlook 2007 can be configured to get through a Proxy to make a HTTP connection to an external mail server?

Surely there must be a way that Outlook can be configured to use the Internet Explorer proxy settings, without needing to modify ISA?

Take FTP tools, etc, for example, that only need to know what the Proxy server is, and the authentication details to get through it. They dont require ISA to be modified to allow them through (obviously as long as FTP is configured as an allowed protocol / port).

Short of installing an "unauthorised 3rd party mail application" on my work PC, there must surely be an answer to this that doesn't need ISA modification made when the traffic is HTTP based?
Apr 8, 2019
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Yes its working fine and we are using webproxy.
Just create an access rule that allows a User-Defined Port of 3535 from Internal Network to External Network.
Also don't forget to change the following:
1. Mail Client's outgoing port to 3535.
2. Clients PC's firewall to allow port 3535. If Windows goto Control Panel>Windows Firewall>Advance Settings>Outbound Rules:
a. Create a New Rule>Port>Select TCP>Specific remote ports: 3535>Allow the connection>Check Domain,Private and Public>Name it :)>Done.

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