Installation media, such as a USB flash drive, can be used to install a new copy of Windows, perform a clean installation of Windows, or reinstall Windows. To create installation media, go to the software download website, where step-by-step instructions can be found.

Some Office 2019, Office 2016, and Office 2013 products come with a product key. If yours did, before installing Microsoft 365 for the first time, sign in with an existing or new Microsoft account and enter your product key at office.com/setup. Redeeming your key is what links your account with Microsoft 365 so you only have to do this once.

若要在 Microsoft Edge 中更改默认搜索引擎：. 使用要设置为默认值的搜索引擎在地址栏中执行搜索。. 依次选择“ 设置及更多 ” >“ 设置 ”。. 选择 隐私、搜索、服务。. 向下滚动到“ 服务 ”部分，然后选择“ 地址栏和搜索 ”。. 在“地址栏中使用的搜索引擎 ...

Codecs allow you to play different formats of audio and video files. Media Player supports a wide variety of codecs. Most are included out of the box; some additional codecs can be installed from the Microsoft Store.

However, you can change the default search engine to any site that uses OpenSearch technology. To change your default search engine in Microsoft Edge: Perform a search in the address bar using the search engine you want to set as your default. Select Settings and more > Settings .

You can start a scan for malware any time you like. Note: Microsoft Defender currently offers anti-malware on Windows, Android, and macOS. From the Microsoft Defender dashboard. If you want a deeper scan, instead of selecting Quick scan in step 3, select Scan options and choose the type of scan you want.

You can view and clear your Microsoft Edge browsing history stored on a single device, across all synced devices, and in the cloud. You may choose to clear your browsing history at any time.

Change from a 32-bit version to a 64-bit version or vice versa. Activate Windows. Fix Bluetooth problems in Windows. Learn how to install, reinstall, or activate Microsoft 365 or Office 2019 on a PC or Mac.

Customer service phone numbers. For help, follow the Get help link below. Describe your problem, and we'll provide self-help or connect you to the most appropriate support, which may include chat or request a call — we’ll call you, so you don’t have to wait.

Help for admins of small businesses. Contact Microsoft Support. Find solutions to common problems, or get help from a support agent.