I used Outlook 2010 and Outlook 2013 as my desktop email client because they were nearly free. Employees of my employer got the Office Suites for a nominal charge. (my employer rolled back to Word 2010, and Outlook 2010 connected to its MS Exchange server for a time). The programs did what I needed. I had a server account at my ISP. Outlook connected with the server using POP3, a version of Post Office Protocol. I began to consider letting go of my ISP after giving up the cable box and cable TV. This may mean I give up email account and address when I give up the Cable ISP service, and go with a new service. This meant thinking about a new email address on a webmail service, and a new email client.
Outlook was and it a message user agent (client) for Microsoft Exchange Server using proprietary MAPI protocols. In the enterprize enviroment a client connects to the enterprize email server which stores messages and connects to the Internet. Outlook has the capability to manage local copies of messages in a PST file (a dedicated database), which lets it function as a standalone internet email client. Contrary to MS Outlook 2013 Support articles and publicity about Hotmail Connector and Exchange Active Sync,Outlook 2013 did not easily support connecting to an Outlook.com account. After MS “improved” Outlook, creating a lock-in effect for its Hotmail/Outlook.com services and more of a walled garden or closed platform approach to services.
Outlook 2013 does not easily support IMAP. The capability may be there. For instance, there are resources that explain making an IMAP connection in Outlook, which may work or may have been outdated by changes in Windows and the Office Suite. Searching for ways to adapt Outlook 2013 is frustrating and time consuming. This makes using Outlook with webmail platforms other than Hotmail/Outlook difficult. Outlook 2013 has already started its spiral into obsolesence. Newer versions have been web/cloud based (software as a service), which leaves MS with a stream of income as long as consumers will stay with MS as rentier. Staying with Outlook as client means subscribing, which will not be cheap, and being locked in.
There are desktop email clients that support IMAP, and downloading and local storage of messages. IMAP is a robust standard, even if Microsoft deprecates it. It works with webmail, although it is a conceptual leap from POP, and requires some management. Time to move on.