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If you want to use 64-bit guest support on a 32-bit host operating system, you must also select a 64-bit operating system for the particular VM.
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You must enable hardware virtualization for the particular VM for which you want 64-bit support software virtualization is not supported for 64-bit VMs. You need a 64-bit processor with hardware virtualization support (see the section called “ Hardware vs. VirtualBox supports 64-bit guest operating systems, even on 32-bit host operating systems, provided that the following conditions are met: Here is the official documentation about 64 bit OS: To allow installing 64 bit OS on VirtualBox. But sometimes, 64 bit OS is wanted for specific uses such as running platform specific tests.
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By default, VirtualBox only allows to install 32 bit OS on it.
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