There is no internet connection in the virtual machine after updating Parallels Tools.
3rd party network related drivers presence.
In Windows press CMD (Win) + R buttons > in the appeared search bar type in devmgmt.msc > click OK, it will get you to Device Manager
Unwrap and check Network adapters and Other devices tabs contents, if you see any drivers with a yellow exclamation mark or if these adapters are not in the list of the built-in Parallels network adapters, please right click them and click Uninstall.
- Install Parallels Tools again.