Hi,
Thanks for posting your query on Microsoft Community and we apologize for delay in response.
To assist you better, please provide few details.
1) Do you receive any error message, while to scan full system?
Jan 09, 2019 In the left pane of Task Scheduler, expand Task Scheduler Library Microsoft Windows and then scroll down and double-click the Windows Defender folder. In the top-center pane, double-click Windows Defender Scheduled Scan. Select the Triggers tab, and then select New. Set your time and frequency, and then select OK. Mar 10, 2017 How to Manually Download and Install Windows Defender Update in Windows 10 Music by: And So It Begins by Artificial Music (Royalty Free Music) Link: https://.
Download Windows Defender Antivirus
2) Have you installed any other antivirus on your computer?
I would suggest you to try the below steps and check if it helps.
Step 1: Perform System File Checker (sfc) scan.
System File Checker is a utility in Windows that allows users to scan for corruptions in Windows system files and restore corrupted files.
To perform SFC Scan, refer to the below link:
Note: Steps mentioned for Windows 8/8.1, will work fine with Windows 10.
Step 2:
To change the default download location in Microsoft Edge Browser.
Open File Explorer.
Right click on Downloads and select Properties.
Select Location tab and click Move and then select where you want to have your downloads to be saved.
For more information about Microsoft Edge browser, refer to the below link:
Window 10 Defender Update Download
Hope it helps, reply to us with the status of your issue. We will be happy to assist you.