Pop3 is disabled by default on Office365, you can, however, enable this from your Global Administrator portal (the link is in your nvArea) using the following steps.
First, to login to your Global Administrator portal, once you login to the nvArea, click on Hosting Services, Manage Hosting.
Click on your Office365 account.
Once in there, you will see the link and login details for the Global Administrator portal.
Select Settings > View all Outlook settings > Mail > Sync email.
- Under POP and IMAP, select Yes under Let devices and apps use POP.