
While I am no expert, the error occurs when the selected ISO file has only ISO9660 file system and missing UDF and Joliet.


Please select a valid ISO file and try again” error. Windows 7 USB/DVD Download Tool sports an easy-to-use interface and is compatible with Windows 8/8.1 as well as the latest Windows 10 but at times when you open Windows ISO file by clicking the Browse button, the tool shows “The selected file is not a valid ISO file.
