If you have tried to create a Windows 7 bootable USB using the microsoft tool then you might have got this error “The selected file is not a valid ISO file. Please Select a valid ISO file and try again ” .

To solve this problem you can use PowerISO full version :

• Open the ISO using PowerISO .
• Then go to the file-> Image Properties :

• Now you click on Image Properties and then click on the UDF checkbox .

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• Now save the ISO file .
• Again open the DVD USB tool and now you can create you bootable DVD or bootable pendrive easily .