Installing Windows 7 on an external HDD can be a bit tricky due to various limitations and compatibility issues. Let's address your questions and the issues you encountered during the installation: 1. Installing Windows 7 on External HDD: - Yes, it is possible to install Windows 7 on an external HDD, but there are certain challenges, as you've experienced. - Installing Windows on an eSATA drive can be complicated because Windows might not detect the drive during the initial setup due to driver loading timing. - To work around this issue, you successfully loaded the driver for the eSATA controller using a flash drive before the setup. This is a common workaround for such situations. - The warning about the drive not being bootable could be due to the drive not being set as the primary boot drive in the BIOS. Ensuring the eHDD is set as the primary boot device may resolve this warning. 2. Acer Aspire 6920G SATA Ports: - The Acer Aspire 6920G typically comes with two internal SATA ports. If you need to connect additional SATA devices like an external HDD, you might consider using an eSATA port if available. 3. Loading Drivers Before Windows 7 Starts Loading: - Given your specific scenario where the drive is not detected after selecting Windows 7 as the OS to run, loading drivers before Windows starts loading is crucial. - One approach is to create a startup disk or flash drive that contains the necessary drivers for the eSATA or USB controller. - By loading these drivers early in the installation process, you can ensure that Windows recognizes the external HDD correctly. 4. BSOD (Blue Screen of Death) Errors: - The BSOD flashing for a brief moment could be caused by various issues, including driver conflicts or hardware compatibility problems. - Hanging up on disk.sys during safe mode loading indicates a potential issue with the disk driver. To address the BSOD and loading issues, creating a startup disk with the correct drivers is a good step. Additionally, ensuring that the drivers are compatible with your hardware and Windows 7 is essential for a successful installation on an external HDD. If you encounter further challenges or need assistance with specific steps or driver compatibility, feel free to provide more details for additional guidance.