Some users on Windows 7 or Windows 8 have reported that they are unable to start Anki on their system. It is not clear what is causing these problems - it may be that some systems are missing a certain library, or something about their configuration is not compatible with the libraries recent versions are built with.
If you are not able to update to Windows 10 at the moment, please download the older 2.1.15 version. It is built with older libraries, and should work on most systems where the latest release does not. Please uninstall the current version before installing 2.1.15.