First search your drive for .ost files.
Those are the files Outlook uses for offline data.
Name(s) should be your various email addresses but with .ost at the end.
E.g. xxxx@comcast.net.ost where xxxx is a specific email account name hosted by comcast.net
Path is probably C:\Users\[username]\AppData\Local\Microsoft\Outlook
Full disclosure: had to do some research and that is what I have discovered/figured out so far.
If you find those file(s), move one to the applicable directory on your current system. By applicable I mean the directory where some existing, working email .ost file exists.
See if the copied in .ost works. If so, move in the other *.ost files.