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Como uma solução geral, você deve considerar alterar as configurações da área de trabalho remota para enviar eventos da chave do Windows para o servidor remoto . Da Microsoft:
If the Remote Desktop Connection dialog box is not already open, open it by typing mstsc on the Start screen, and then pressing Enter.
On the Remote Desktop Connection dialog box, click Show Options to display connection setting tabs.
In the Keyboard area of the Local Resources tab, select one of the following from the Apply Windows key combinations drop-down list.
To apply keyboard shortcuts to a full-screen Remote Desktop session, select Only when using the full screen.
To apply keyboard shortcuts to a Remote Desktop session that is contained within a window, select On the remote computer.
When you are finished configuring other settings for your Remote Desktop session, click Connect to connect to the session and start working, or click Save on the General tab to save your connection settings as an RDP file that you can use for future connections.