How to remove "this computer only" from files

Office 2013, I have used gmail through all window versions for a number of years.

The reason that "This Computer Only" would appear in a folder description is that the account was configured as an IMAP account. An account configured as a POP account would not have these descriptions added to the folders. In addition, IMAP data would be stored in an .ost file (in OL'2013) whereas a POP account would be stored in a .pst file. Again, merely going to/from W10 would have absolutely no bearing on this. 

So next questions.......................... 

Info requested in the following questions is available via File --> Account Settings

#1 - under the <Email tab> - How many email accounts are currently configured and what type is/are the accounts (type listed in right-hand column (i.e. POP, Imap etc)

#2 - under the <Data Files tab> - how many data files are listed and what are each of their extensions (specifically - .ost or .pst)

#3 - Was anything exported and/or imported somewhere along the line? 

To save some time.....................if your email account is currently configured as an IMAP account - your contact/calendar/journal/notes/tasks/sync issues folders are going to have "This Computer Only" - none of the email folders should have that descriptor. If that's the case - there is nothing to fix since that's exactly the way it works. Anything else, then "stuff happened" somewhere along the line and it wouldn't have been anything added by Outlook on its own. If your account is configured as a POP account - there would be no way any of the folders would have "This computer only" in the description without some kind of manual intervention.