How to manage Kerberos KDC usage of RC4 for service account ticket issuance changes related to CVE-2026-20833

Contact Microsoft Support. Find solutions to common problems, or get help from a support agent.

Junk email can strain networks, clog email servers, and fill mailboxes with unwanted messages and images. The server that hosts your mailbox will filter out most junk email, but not always all of it. The light version of Outlook Web App helps you control unwanted and unsolicited messages by letting you manage and create lists of trusted and untrusted email addresses and domains.

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Here are the most likely causes for an unrecognized charge: A Microsoft subscription has recurring billing enabled. Someone you know, such as a family member, bought something with your card. You can now investigate this on the Manage your payments page. A previously declined charge was charged again. A pre-order or split order was shipped. Someone made an in-app purchase from an app, game, or ...

Important: You don't need to remove old security information unless there is an account security risk (e.g. someone else has access to your old mailbox). If you do need to replace your security information, make sure you add new information first. If you request removal of all security information in your account, the account is put into a restricted state for 30-days. Your information doesn't ...

Microsoft prioritizes account security and works to prevent people from signing in without your permission. When we notice a sign-in attempt from a new location or device, we help protect the account by sending you an email message and an SMS alert. If your phone number or email changes, it's important to promptly update the security contact info on the Security basics page so we can work with ...

A phishing email is an email that appears legitimate but is actually an attempt to get your personal information or steal your money. Some deceptive emails appear to be from a safe sender but, in fact, have a "spoofed" source address to fool you. Here are some ways to deal with phishing and spoofing scams in Outlook.com. Spoof intelligence in Exchange Online Protection helps prevent phishing ...

You can block messages from specific email addresses or domains from reaching your inbox. When you add an email address or domain to your blocked senders list, Outlook automatically moves messages from that sender to the Junk Email folder. When you block an account in Outlook, it will not appear in Teams people picking and search unless you have interacted with that account in Teams. You can ...

Learn how to protect your PC, identity, and data from tech support scams.