Using OST files

I have a couple of old OST files from company email addresses I previously used. I need access to the emails in those files quite often so find myself opening up Outlook often. My problem is that Outlook attempts to sync with those dormant accounts and I thus have to cancel out of multiple login screens every time I go into Outlook. So, my question is if there is a way to instruct Outlook not to poll those accounts, ie no sending or receiving ever. I found some menus to tell it to only manually do a send/receive, but that didn't seem to do the trick since the login screen keeps popping up prompting me to enter a password.

I am using a desktop version of Office called Microsoft 365

Thanks in advance for any guidance on this!