Paint.net 1603 Error

The paint.net 1603 error occurs during installation of the popular graphics program.  To fix this installation error make sure that the required Microsoft .NET framework is installed on your computer.  A particular version of the framework may be necessary for older paint.net versions.  Having the latest .NET Framework for example is not necessarily sufficient if the paint.net version being installed requires an older one.  In Windows check in Control Panel > Programs > Uninstall a Program and look for "Microsoft .NET Framework" to see if it is installed on your system. Installing the latest beta development build of paint.net installs the .NET framework files automatically and is probably worth trying if the stable build of paint.net refuses to install.