If you get the message "Please check your Internet connection" after launching Dashlane on your computer, there may be a conflict with a proxy, firewall, or any anti-virus software you use, or else a conflict with your internet settings.
First, make sure that you have properly set up any proxy or firewall that you may be using on your computer. If you are unsure of whether you have a proxy or firewall, you can check by going to Control Panel > Network and Internet > Network and Sharing Center on Windows.
If you're using a firewall, please make sure that it is not blocking Dashlane.
Proxies are normally used for networks in a company. Unfortunately, there are many proxies that we do not support yet, including some authenticating proxies. If this is the case, remember that you can access your account via the Web app.
Also, you may want to check if your anti-virus software is included among those mentioned here. If so, configure it by following the instructions outlined in that article.
If you're not using a proxy or firewall but you're still having a connection problem, then you might need to change your Internet settings. Once you have checked that there is no proxy running, please go to Control Panel > Network and Internet > Internet Options > Connections > LAN Settings and disable all the options.