Make sure that you have SafeInCloud desktop app installed and running.
Tip: You do not need to unlock the app. It just has to be running in the background.
Tip: Get the desktop app for Windows or Mac for free from https://www.safe-in-cloud.com/download
Make sure that your proxy settings set to bypass the local addresses.
- Open Internet Options in the Control Panel;
- Select the Connections tab;
- Press the LAN settings button;
- Check Bypass proxy server for local addresses (if this setting is enabled).
- Open Network in the System Preferences;
- Press the Advanced… button;
- Select the Proxies tab;
- Add *.local to the Bypass proxy settings edit field.
Try to temporary disable all other 3rd party extensions in your browser. If the problem is solved, then turn them on one-by-one to identify an extension that causes the error. Usually these are extensions related to VPN, ad-blocking, or privacy protection. Add an exception for localhost:19756 in the options of this extension. This is the port that SafeInCloud uses for the communication.