Outlook account not updating
I have two IMAP accounts in my Outlook 2013 and neither one of them updates as fast I remember from previous versions. POP accounts connect to the server, download the messages, & then disconnect.
I will always hear my phone's email alert before Outlook shows new mail. IMAP accounts maintain the connection to the server, but they still have to perform a "send/receive" action to download the new headers from the server.
Suddenly WLM stopped syncing your emails and started showing error messages.
Now you can't sync your Microsoft account emails using Windows Live Mail program.
Apparent gaps will be magically healed as Mail app caches the entire Inbox.
This seemingly endless trip to the bottom of your Inbox is tedious, but it really does set things straight.
My emails in Outlook have not updated since Tuesday April 4, 2017.
However when I check my emails through the carriers webmail server all the new emails are there. I have the strong feeling if I reinstall outlook 16 I will lose all my emails.
Well by your description it sounds like you have a POP email account.
A tweak to Microsoft's cloud service has blocked a good number of people from accessing their messages.
Specifically, the baffling and unannounced change affects users with connected accounts: these are email accounts hosted on third-party servers (such as a company's private server or an ISP's mail server) that are accessed via the cloud.