I created a fedora VM on Lubuntu host this afternoon. When I reopen it tonight, I found the network icon on the top-right disappeared and the network function failed too. I tried some solutions on the forum but nothing helped. Therefore I stopped to do something else. When I came back to VMplayer and tried to open the VM file again, I found that there was my “Fedora” folder along with an empty “fedora” folder under the same path, so I think it maybe the duplicated file name which played the trick. I deleted the empty file and opened the VM again, Now the problem is gone.