Hi, Anubhav. I'm sorry to hear you're having this problem, and I hope I can assist you to find a satisfactory solution.
I suggest checking that there are no corrupted system files, that other software may be interfering and that there is no malware.
Run System File Checker (SFC) and DISM
Corrupted system files can cause .NET Framework issues. Running SFC and DISM can help repair them.
Open Command Prompt as Administrator:
Press Win + X and select Command Prompt (Admin) or Windows PowerShell (Admin).
Run SFC:
sfc /scannow
Run DISM if SFC finds issues:
DISM /Online /Cleanup-Image /RestoreHealth
Perform a Clean Boot
A clean boot can help you determine if background programs are interfering with .NET Framework.
Press Win + R, type msconfig and press Enter.
Go to the Services tab.
Check Hide all Microsoft services and then click Disable all.
Go to the Startup tab and click Open Task Manager.
Disable all startup items.
Restart your computer and see if the issue persists.
Check for Malware
Malware can cause various issues including .NET Framework errors.
Run a full system scan with your antivirus software.
Use additional tools like Malwarebytes for a thorough check.