Ensure you are using a high-speed USB 2.0 port; the Astra 5800 sometimes struggles with USB 3.0 (blue) ports. If you'd like to try the manual setup, I can help you: Walk through Device Manager steps to identify the hardware ID. Explain how to disable Driver Signature Enforcement in Windows 7. modern alternative scanner if this one is too far gone. for the manual driver injection?
No 64-bit driver is loaded in the host – all scanning occurs in the VM. Slower, but works. Umax Astra 5800 Scanner Driver For Windows 7 64 Bit -UPD-