I had exactly the same problem, I bought a 5pc license and it is working fine on 1 desktop and 2 laptops, all running Avast Premium. However not matter what I tried, on laptop #4 I kept getting the message "
Sorry, the secureline VPN server has refused your license file". Even though the Avast control panel under "Subscriptions" stated that the license was active and still had 320 days on it.
Twice I uninstall VPN from Avast Premium and re-installed it.
I re-installed the License app twice ... and even though I did get the message that it was successful and that the app was activated it still did not accept the license file when trying to connect to the VPN server.
I uninstalled and reinstalled Avast Premium ... still the same problem.
I do not really remember what else I tried, but it does not matter it didn't work anyway.
Then I decided to uninstall it from Avast Premier, and download and install the stand-alone app at (
https://support.avast.com/en-us/article/80/ ).
This did the trick. It accepted the License without a problem and connected to the VPN server within seconds.
I hope this will also help someone else with this problem.
All the best and good luck
P.S. The only issue with this solution I have is that Avast Premium interface keeps telling me that my privacy is not protected and keeps referring me to the VPN License purchase site, but the Network indicator shows that I am connected through the VPN Server ("Unidentified network - Internet access). But this is a minor issue that does not seem to affect the performance.