Windows 7 Guest on a VirtualBox host at default will deem you without internet and without audio. For the internet, do the following:
Right click over the Machine Name in VirtualBox Interface > Settings > Network > Adapter 1 > Advanced > Adapter Type = Intel PRO/1000 MT Desktop (82540EM)
For the audio, head over to here for the AC’97 Realtek drivers: https://www.download3k.com/Install-Realtek-AC-97-Vista-Driver.html
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