Cast to a display from a Windows PC. You can wirelessly connect your PC to a TV, projector, or other kind of external display that supports Miracast. Turn on your TV, projector, or other display. If you're using a Miracast dongle or adapter, make sure it's plugged in to the display.

Contact Support. For technical support, go to Contact Microsoft Support, enter your problem and select Get Help. If you still need help, select Contact Support to be routed to the best support option. Learn how to manage your Microsoft account security info and troubleshoot verification code issues.

If you can't sign in to your Outlook.com, Hotmail, Live, or MSN email account, or you're not sure how to sign in or sign out, here are some solutions.

If your system is asking you for your BitLocker recovery key, the following information may help you locate your recovery key and understand why you're being asked to provide it. Important: Microsoft support is unable to provide, or recreate, a lost BitLocker recovery key.

The Microsoft Authenticator app helps you sign into your accounts when you're using two-step verification.

Add, remove or update an email address or phone number. If you want to make changes to the email addresses or phone numbers associated with your Microsoft account, use our guided support tool below to help you update the right information in the right way.

Go to the Microsoft account sign-in page at https://account.microsoft.com and enter your email address. If you see a message that says "We couldn't find an account with that username." or "That Microsoft account doesn't exist", then the address you entered is not a Microsoft account. If you believe it should be:

Learn how to update drivers in Windows using Device Manager to update or reinstall a driver.

Hotmail is now Outlook.com. Learn how to sign in to access your Outlook.com, Hotmail, Live, or MSN email account.

其实用查找函数很容易做到。. VLOOKUP 和 HLOOKUP 函数，以及 INDEX 和 MATCH 是 Excel 中一些最有用的函数。. 注意: Excel 中不再提供“查找向导”功能。. 下面是如何使用 VLOOKUP 的示例。. =VLOOKUP (B2,C2:E7,3,TRUE) 在此示例中，B2 是第一个 参数 ，即函数运行所需的数据元素 ...