My first attempt to start using Outlook after an absence of over 12 months was motivated by the need to have common data (calendars, contacts) between 3 PC's. I was offered the use of an Exchanger server account an then proceeded to incorporate my existing Yahoo IMAP account within it. I no longer wish to use the Exchange server scenario because the login success was intermittent and so I removed the local account, deleted the associated data file and removed the profile. I created a new profile which I visibly associated only with the IMAP account but Outlook insists on creating an OST data file. The data sync software I purchased will only sync PST however. Is there some leftover item from a previous setup which is still trying to use the Exchange server ? All references I have read suggest that POP3 and IMAP should result in PST, mine does not !