Michael Kang's Blog

As cygwin doesn’t supply uninstaller, the whole uninstall process should be done manually.

1. Stop any service if running.
2. Delete cygwin folder. (\cygwin)
3. Delete cygwin install file folder.
4. Delete 2 registry keys.
   HKLM\Software\Cygnus Solutions
   HKU\S-1-5-21-1801674531-2077806209-2146658873-1004\Software\Cygnus Solutions