You're welcome.
Sorry I have just read your first post (I should have read it first as I thought this was a firewall issue):
After having subscribed and activated protection, I had noticed that my browser (Opera for PC, latest version) wouldn't access to the Internet anymore. I searched for a reason and tried to deactivate Avast Web Shield: it worked!
How does this present itself, e.g. does it give an error message (if so can you post a screenshot) or does it just not connect ?
What happens if you disable https scanning in the web shield settings, does it work then ?
If you are using a different browser and the web shield is enabled does that work ?
Unfortunately I use Firefox as my browser of choice and that is fine with Avast Free and the Web Shield enabled.