If you have installed a previous version of the firmware upgrade, you may still need to manually uninstall the old files. 


To do this: 

Go to Control Panel --> Programs and Features --> UpgradeFirmware_V..... --> Uninstall


After uninstalling old versions of the firmware, try to download the firmware again. 


If the download is still unsuccessful, please send an email to hdmsupport@hdmusa.com to open a new support ticket for assistance.