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[Wainuitech]

Yes you can move them,  ( and upload to IMAP), depending on how much you have it can take several hours to sync.

This is a good time to do clean outs, you know the times when we all will get around to it

1st and most important, go to your .pst file & make a backup copy.  This way If anything does go wrong you wont lose any mails.  Will also pay to backup your contacts.
Here is a  set of instructions,

Only Difference I do is go directly to the.pst file , normally in Documents/ Outlook Files  and copy/paste it to save

Number 4 I do differently ( but it does work)

https://help.one.com/hc/en-us/articles/3...OP-to-IMAP

Edited in:  To setup a New IMAP account some places go about it the long way ( manually) This article is how it works 99% of the time, Bascically Outlook does all the work /settings, only thing you need to know is your email address and password.

https://help.one.com/hc/en-us/articles/115005594485

IF you need to enter the settings manually they are listed in this link, they did change a while back to these 
https://support.microsoft.com/en-gb/offi...6c4ac95353

How I import the old .pst is shown in  the following article, near the bottom - "Restore Your mail Box"

https://www.hostpapa.com/knowledgebase/c...p-outlook/