It's most likely your firewall and it sounds like your antiviris is stopping it.
Follow these steps and hopefully it will work again and allow Achat and the updater through your windows and antivirus firewalls.
Search your PC for “Allow applications through windows defender firewall “
Click on change settings, top right
click on “allow another application” bottom right
Search for Achat and click on it. Then add the things:
AChat_setup.exe
Achat_starter
Achat version updater.exe
Add them one by one and click ok so they are allowed through your Wndows Defender Firewall.
Then do the same type of thing by going into your own antivirus firewall settings to add them as well.
Search for allow application or allow programme and follow the same kind of steps.
Hope this works for you.
Achats Tom advises to uninstall Achat completely and install from this link.
Here you can find an up to date full version with some corrections:
https://funnyadultgamesplay.com/versions/AChat_setup.exe
If you uninstall the existing program and install this new version it can solve the upgrade problem.
This contains all upgrades till Jan 9, 2020
