Hi, I’m using Windows 7 and I installed the program CCleaner. When I first ran CCleaner, there were normal ads and some antivirus ads (AVs). I wanted to read the ads, so I clicked on the topic name of the antivirus ads. After I clicked on it (I’m not sure if it was through Internet Explorer), a program called SmartScreen popped up, asking me if I wanted to save a file. The file didn’t have a name or any visible information, making it seem like it was trying to download something with no name
SmartScreen is a part of Windows Security.
I suspect that it wasn’t sure about the Content Delivery Network “Avcdn.net” used by CCleaner to download certain things.
That CDN is quite often flagged up by some secutity filters as being ‘suspicious’ when what they actually mean is ‘we’re not sure if it’s suspicious or not, so we’ll let you decide’.
Windows SmartScreen Filter will flag it sometimes, but most other times not.
Or it may have regarded the download file itself as a PUP/PUA (Potentially Unwanted Program/Potentially Unwanted Aplication) so was asking if you really wanted it.
Again it can be variable whether it does that or not.
Why it was not showing you a name is another question, but that may just be due to Win7 getting pretty old now.
However if you can’t see whatever it is that SmartScreen has flagged then you are probably safest to reject it.
The AV’s that CCleaner will offer you are either Avast or AVG - they are both from Avast and so are basically the same thing with a different user interface.
(Norton is also now in the same group of companies, but I’ve not heard of CCleaner offering a Norton AV, yet).
More about SmartScreen: Microsoft SmartScreen - Wikipedia
More about SmartScreen in Win7, and how to turn it Off/On (if you want to):
https://www.sevenforums.com/tutorials/1406-internet-explorer-smartscreen-filter-turn-off.html