If Windows Defender Security Center doesn’t open, can’t update the definition file, or can’t finish scanning for viruses, try running Windows Defender in Offline Mode, which is explained below in To scan for malware and viruses with Windows Defender Offline (Windows 10 Version 1803).

Note: If it’s been fewer than 10 days since you upgraded to Windows 10, your previous version of Windows will be listed as a system file you can delete.If you need to free up drive space, you can delete it, but keep in mind that you'll be deleting your Windows.old folder, which contains files that give you the option to go back to your previous version of Windows.

Swipe in from the right edge of the screen, and then tap Search.Or, if you are using a mouse, point to the lower-right corner of the screen, and then click Search.Type Command Prompt in the Search box, right-click Command Prompt, and then click Run as administrator.If you are prompted for an administrator password or for a confirmation, type the password, or click Allow.

If you don't see your firmware developer listed, refer to your device documentation. AMI. Refer to your device's firmware documentation. Phoenix. Refer to your device's firmware documentation. Step three: Turn on Virtual Machine Platform in Windows. These instructions may apply if you upgraded your PC from Windows 10 to Windows 11.

若要在 Outlook.com 中获取支持，请单击此处或选择菜单栏上的帮助，然后输入查询。 如果自助服务无法解决问题，请向下滚动到“仍需要帮助？”，然后选择“是”。 若要在 Outlook.com 中联系我们，需要登录。

In the upper left corner of the window, select the app launcher > All apps > SharePoint Tip: If you don't see the SharePoint app under All apps, use the Search box near the top of the window to search for SharePoint.

If Microsoft 365 can't activate, it eventually becomes unlicensed and all editing features of Microsoft 365 are disabled. Microsoft can become unlicensed for a number of reasons. For example, if your Microsoft 365 subscription expires, you must renew your subscription to restore all features of Microsoft 365. ...

Windows Photo Viewer isn't part of Windows 10, but if you upgraded from Windows 7 or Windows 8.1, you might still have it. To check, press and hold (or right-click) a photo in File Explorer, and select Open with.If Windows Photo Viewer isn't in the list, you cannot install it on Windows 10.

Note: If you can't open an app to check your installation type, try the more common Click-to-Run or MSI uninstall steps first. Create or open an existing file and select File > Account (or it might say Office Account). Under Product information, find the About button and check for the following:

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