Windows 10: Unable to open Windows Security

I have upgraded Windows 10 to Windows 11. Every thing is smooth. Only difficulty is with Windows Security Defender, The same is not opening in Windows11, It is asking to open and confirm Microsoft soft Account which I have Closed. My other User active Administrator Account is working and available. There is no provision to to amend it. Help is needed. For frequent Scanning should I install some other scanner [Original Title: Windows Security Defender]

:)

 

Windows 10 Tweaks

Pressing “Windows+Pause Break” (it’s up there next to scroll lock) opens the “System” Window.

Windows 10: In the new version of Windows, Explorer has a section called Quick Access. This includes your frequent folders and recent files. Explorer defaults to opening this page when you open a new window. If you’d rather open the usual This PC, with links to your drives and library folders, follow these steps:

• Open a new Explorer window.
• Click View in the ribbon.
• Click Options.
• Under General, next to “Open File Explorer to:” choose “This PC.”
• Click OK

credit to Lifehacker.

 

windows defender & security center services keep turning off


Are you running any other AV or did you have one running in the past? If you didn't use an uninstaller for the AV, then the remnants of it could be causing the problem. Normally any time you install an AV it disables Defender by default.

If you are getting any error codes please list those, that will be helpful in helping you.

As torre suggested, might be a good idea to do a reset or even a reinstall.

Reset Windows 10 - Windows 10 Forums

Windows 10 - Clean Install - Windows 10 Forums

There are also some suggestions listed here:

Unable to turn on Windows Defender in Windows 7 / 8 / 10

 

Unable to open a Secure PDF sent by email on the Windows 8 Phone

Hi Paul Philly,

Fortunately, Microsoft is listening. While I am unable to test a Secured PDF to confirm, I trust that you have tried Secured PDF's from several different sources. If this is the case and you find yourself unable to open any Secured PDFs from a variety
of sources, then I want to refer you to the
Windows Phone Feature Suggestions box.

As to attaching documents, you can simply save your documents to your free 7 GBs of storage called SkyDrive. Then, on your device, use the SkyDrive app to browse to the document, tap and hold until a menu appears. From this menu, you can share the document:

• send a link in email (View only or View and edit)
• copy link to clipboard
• permission

Choosing the first option will allow you to generate an email, send the link and add any personal comments you'd like to send with the document. While this is a little different from the traditional desktop method, mobile devices are limited in storage
space and need cloud-based services to assist you in being more productive.

I hope this helps!

David