Open Outlook and select File.
Click Add Account.
Check Manually configure server settings or additional server types
Select Internet E-mail
Enter Your Name and E-mail Address
Choose IMAP as your account type
For Incoming mail server (IMAP), enter imap.one.com. For Outgoing mail server (SMTP), enter send.one.com
In Logon Information enter the e-mail address and password that you created in the control panel
Configuration of the SMTP server in Outlook 2010
Click More Settings
Select Outgoing Server and then My outgoing server (SMTP) requires authentication
For Incoming server (IMAP) enter 993 and select SSL.
For Outgoing server (SMTP) enter 465 and select SSL.
For Root folder path enter INBOX with uppercase letters.