For those unfamiliar, PUAs aren’t necessarily considered to be malware or particularly dangerous, at least not in the sense that it could destroy your computer and steal your files. Instead, PUAs can refer to apps like adware or apps that might have a negative impact on your privacy, which is why in some cases, Microsoft might block or warn users when it detects such an app.
The feature was introduced in the May 2020 update, but Microsoft has announced that starting in August 2021, it will be enabled by default. According to Microsoft, “In the Windows 10 May 2020 Update we added Potentially Unwanted App blocking for everyone running Windows 10, but customers who wanted to use it still had to turn it on. Starting in early August 2021 we’ll begin turning it on by default to make it easier for you to keep your systems performing at their best.”
For those who already turned it on, you don’t have to do anything, but for those who left it off, the August update will enable it so you might have to disable it if there are certain apps you want to install but are being blocked by Windows.