Microsoft 365 is the subscription copy of Outlook. It has the same File tab as the boxed versions, so these steps match what Microsoft's own page shows for classic Outlook on Windows. If your Outlook has no File tab, you are in the new Outlook, and that one is a different article.
Steps
- Confirm you are in classic Outlook
Look at the top left of the window. A File tab means classic Outlook. No File tab and a gear icon in the top right means the new Outlook, which Microsoft says does not take POP accounts. Use the new Outlook article for that case.
- Select File, then Add Account
Microsoft's page names these two clicks for classic Outlook. A small box opens asking for an email address.
- Type your full address, then open Advanced options
Enter the whole address, such as name@yourdomain.com. Select Advanced options under the box, and tick Let me set up my account manually. Without that tick Outlook tries IMAP first and fails.
- Select Connect and choose POP
Outlook lists account types next. Microsoft notes that IMAP is the usual choice for most providers, but POP is also offered. High Desert Internet mail is POP3, so pick POP.
- Type the two server names
Incoming mail server: pop.hdiss.net. Outgoing mail server: smtp.hdiss.net. Your user name is your full email address.
- Ask us for the port and encryption values
Outlook pre-fills these boxes with common numbers, and the numbers may not fit your account. The port numbers and the encryption type are not published on this site, so call 775-575-9593 and a person will read you the values for your account.
- Turn on authentication for outgoing mail
Open More Settings, go to the outgoing server section, and turn on authentication for SMTP. Microsoft's POP and IMAP settings page describes this step. Without it, mail can arrive but will not send.
- Enter your password and finish
Select Next, type your email password when asked, and select Connect. When Outlook says the account was added, send yourself a short test message.
How do I know I have Microsoft 365 and not Outlook 2021?
Choose File, then Office Account. Microsoft's page says Product Information there shows the version. A subscription copy names Microsoft 365 Apps. A boxed copy names the year. If you see 2021 or 2024, use the Outlook 2021 and 2024 article. The broader sorting page is Outlook setup for High Desert Internet email.
What if Outlook sends me to the new Outlook?
The new Outlook does not document a way to add POP accounts, and Microsoft's account page sends anyone who needs POP to classic Outlook. If your hdiss.net account will not appear after a switch, go back to classic Outlook or read your mail in webmail in the meantime.
Where do I change a setting later?
In classic Outlook, Microsoft's POP and IMAP page points to the account's More Settings, where the Advanced tab holds the port and encryption boxes. Mail kept in a data file stays on this computer, so read keeping email when you change devices before you remove an account.
Do I need to go outside or touch the antenna for this?
Nothing on this page needs you to go outside. Never climb to the antenna or touch the outdoor radio or its cable; call and a technician comes to the house.
Sources
- support.microsoft.com/en-us/office/add-an-email-account-to-outlook-6e27792a-9267-4aa4-8bb6 (Microsoft, Add an email account to Outlook for Windows, classic Outlook tab, read 2026-10-15)
- support.microsoft.com/en-us/outlook/pop-and-imap-account-settings (Microsoft, POP and IMAP account settings, read 2026-10-15)
- support.microsoft.com/en-us/outlook/getting-started-with-the-new-outlook-for-windows (Microsoft, Getting started with the new Outlook for Windows, read 2026-10-15)
- hdiss.net/webmail/ (High Desert Internet published server names, read 2026-10-15)