When using Chrome, SonicWall's GUI is not accessible due to a cipher error.
Chrome recently disabled RC4 support and old SonicOS releases were using RC4.
The issue is related to the firmware version used on the SonicWall. You will need to be on the latest SonicOS version to get access to the GUI using Google Chrome.
To upgrade the SonicWall firmware you may try to access the GUI using a old version of the browser like Internet Explorer and enabling the support for RC4, upgrade the firmware and then the GUI will be accessible with all the web browsers.