It seems like you're facing an issue where your Windows 7 RC installation DVD is not being read by your Compaq Presario V3532TU laptop but is being read and installed successfully on your Dell Latitude E6400. This discrepancy could be due to a few reasons, such as hardware compatibility, DVD drive issues, or the DVD itself. Here are some troubleshooting steps and considerations to help you address this issue: 1. Compatibility: Different DVD drives can sometimes have varying levels of compatibility with certain types of discs (e.g., dual-layer DVDs). The DVD drive in your Dell Latitude E6400 might have better compatibility with the Windows 7 RC installation DVD compared to the drive in your Compaq Presario V3532TU. 2. DVD Drive Health: The DVD drive in your Compaq laptop might be experiencing issues that prevent it from reading specific discs correctly. It could be a hardware problem with the drive itself. You could try cleaning the DVD drive lens with a cleaning disc to see if it improves readability. 3. Disc Quality: The Windows 7 RC installation DVD could have some imperfections or errors that make it difficult for certain DVD drives to read. Try using a different DVD or create a new copy of the installation disc to rule out any issues with the disc itself. 4. Boot Sequence: Ensure that the boot sequence in your Compaq laptop is set to read from the DVD drive first when attempting to boot from the installation DVD. This can sometimes cause issues if the DVD drive is not the primary boot device. 5. Drivers: Check if there are any driver updates available for the DVD drive in your Compaq laptop. Updated drivers can sometimes improve the drive’s performance and compatibility. 6. Firmware Updates: Consider checking if there are any firmware updates available for the DVD drive in your Compaq laptop. Updating the drive firmware can sometimes resolve compatibility issues. 7. External DVD Drive: If the issue persists, you could also try using an external USB DVD drive on your Compaq laptop to see if it can successfully read the Windows 7 RC installation DVD. By following these steps, you should be able to troubleshoot and potentially resolve the issue with reading the Windows 7 RC installation DVD on your Compaq laptop. If the problem persists, further investigation into hardware compatibility and drive health may be necessary.