If you're getting a blank chat window like the one in the below screenshot, this is due to backend changes and improvements.

To resolve this, follow these steps:

• Close the Altaro UI
• [V7] Browse to: %localappdata%\Altaro VM Backup
• [V8] Browse to: %localappdata%\Altaro VM Backup\User Data\Default
• Delete the Cache folder
• Open the Altaro UI and you'll now be able to use the LiveChat functionality once again

If the above doesn't solve it, ensure that *.livechatinc.com, *.livechat-static.com are allowed through your firewall. More information here.