Does anyone know if there are limits to the number of pst files a user can have in Outlook 2013? We have a user who treats pst files like folders in the inbox despite us telling them that they shouldn't do that and now they are having performance issues on Outlook. There are over 90 of them. So I was wondering if there are actual limits to the number of files. Size is acceptable, most being fairly small. Biggest I think is 5GB.