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Official releases of 2.06 and later come with a brand new installer. Just run the installer and choose a place to put documents and plugins and it will take care of everything for you. For those of you who have an earlier release installed already, especially if you have added a plugin directory for autoloading of plugins, it is a good idea to remove that installation before running the installer -- even though there are no known problems with it, it is always good to get a clean installation.
The following only applies to old releases, prior to v2.05. sh0dan's [cvs releases] will also work in the following way.
Avisynth consists in its entirety of a single DLL and a few entries in the Registry. Once you've unpacked the distribution archive, just move avisynth.dll to your windows\system directory and double-click the install.reg file. There should be no need to reboot.
To uninstall AviSynth, double-click the uninstall.reg file and remove the avisynth.dll file from windows\system.
