Fix: Outlook error 0x80040900

Error 0x80040900 means that either the server name is incorrect or the ports are incorrect. It is normally difficult for a non-technical customer to quickly find out what the correct email settings would be.

Therefore; as a first step of this guide, please call your ISP if your e-mail is with them to ask about the name servers.

Here’s what you need to know:

POP/IMAP server address and port

SMTP server address and port

Are the two SSL enabled?

Once you have these settings they will look like this, in the example below i am using Gmail’s POP settings:


Once you have the correct settings go to your Outlook Account Properties, and make sure  that the server names, ports and the SSL settings are what you have been provided by the ISP.

You can check your email settings on

Since the issue is very dynamic with settings; i cannot provide exact details of your provider without knowing the Outlook version and the provider.

Kevin Arrows
Kevin is a dynamic and self-motivated information technology professional, with a Thorough knowledge of all facets pertaining to network infrastructure design, implementation and administration. Superior record of delivering simultaneous large-scale mission critical projects on time and under budget.

Expert Tip

Fix: Outlook error 0x80040900

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