Win32 Disk Imager may hang or not respond due to incompatibilities with the Windows operating system used by your computer. It is also possible for the program to have problems when the hardware used for reading your SD card or CF card uses a non-USB interface. Please make sure to use the latest version of Windows 7, 8.1, or 10, as well as using a card reader that uses USB. This could also be due to not having enough free RAM space, so make sure you have enough free RAM. Sometimes, using an older version of Win32 Disk Imager may also solve these problems.