If some Windows functions aren't working or Windows crashes, use the System File Checker to scan Windows and restore your files. Though the steps below might look complicated at first glance, just follow them in order, step-by-step, and we’ll try to get you back on track. Run the System File Checker tool (SFC.exe)

All Outlook Data Files (.pst) and Offline Data Files (.ost) are listed along with the name of the account the files are associated with. If you cannot open your Outlook data file or suspect that the file is damaged, use the Inbox Repair tool (scanpst.exe) to repair errors in the file.

Find your BitLocker recovery key. Windows 11 Windows 10. A BitLocker recovery key is needed when BitLocker can’t automatically unlock an encrypted drive in Windows. This key, which is a 48-digit number, is used to regain access to the drive.

Outlook Data Files (.ost) are used when you have an Exchange account and want to work offline or use or use the default Cached Exchange Mode. This type of data file is also used for accounts that you set up with the Outlook Connector for Outlook.com (formerly Hotmail).

Use the Quick Assist web app to get help with your computer directly from Microsoft support agents. The app connects your computer with the Microsoft support agent’s computer using a remote connection.

A response from the from postmaster@outlook.com, postmaster@microsoft.com, or service.microsoft.com usually means the message you tried to send couldn’t be delivered to one or all the intended recipients. How to fix the issue and resend the message. Review the postmaster message for possible reasons why your message was undeliverable.

The Microsoft Support and Recovery Assistant works by running tests to figure out what's wrong and offers the best solution for the identified problem. It can currently fix Office, Microsoft 365, or Outlook problems.

What it fixes. The troubleshooter helps fix problems that: Corrupt registry keys on 64-bit operating systems. Corrupt registry keys that control the update data. Prevent new programs from being installed. Prevent existing programs from being completely uninstalled or updated.

If you use a POP or IMAP account, then all of your Outlook information is stored in an Outlook data file, also known as a Personal Folders File (.pst). You might also use an Outlook data file to backup messages or store older items to keep the size of your mailbox small.

This feature allows you to access your previously downloaded or synchronized email messages, calendar information, contacts, and tasks without an internet connection. Certain types of accounts, such as POP accounts, store their information in Outlook Data Files (.pst files).