By moving items to an Outlook Data File (.pst) on your computer, you can free up storage space in the mailbox on your mail server.When messages or other Outlook items are saved in an Outlook Data File (.pst), the items are available only on the computer where the file is saved.

Offline Outlook Data File (.ost)Most other account types, such as IMAP accounts, Office 365 accounts, Exchange accounts, and accounts use an Offline Outlook Data File (.ost) file to store a synchronized copy of your mailbox information on your local computer. You can read and compose messages, create appointments, and add contacts. Due to time problem on my machine i changed its CMOS battery, i forgot to change time and now it showing Window expired only safe mode is working without networking. I download win-2003 R enterprise edition n activate for 180 days trial version.

If you're having problems getting shared computer activation to work when you deploy Office 365 ProPlus to shared computers in your organization, try the following to fix the problem.

Mac Microsoft Office Error 0x80004005 Update.

How to activate office on mac