Here’s what consumers have asked with answers from CouchTuner.eu staff and previous consumers.
Assuming Avast is your firewall provider- there should be a place for you to add sites that you deem safe. Check around under your account info and see.
The ads you are seeing are from the sites couchtunher streams from ( NOT Couchtuner itself). First install a good anti-virus firewall. THEN install the latest ad=blocker I used Firefox and I've not had and ad or the sign showing that you need to register, etc. Couchtuner isn't a fake site - it really is FREE
You got tricked! No website, pop-up add or browser notification will warn you if you are infected. Only hoaxes, malware and spyware adds or other malicious intend will do that. The only notification you can trust is the warning or scan result from your own AV/security software.
No- couchtuner isn't illegal, because they do not download videos - they stream from other sites. That's why you pick a channel in the tabs over the video screen. Any pop ups you might get are from those other sites - not couchtuner. Get a good ad blocker ( Firefox is free). As long as you are just streaming and not downloading video - it's not illegal.