Here are some rules of thumb for program authors.
Some of them are just best practices/good behaviour, others come from my experiences with rogue software that I migrated from Windows XP to Vista/Windows 7 or had the pleasure to install on some heavily locked down workstations (due to Corporate IT Security):
Do not require administrative privileges for normal execution (initial installation and maybe update installation excluded). This depends of course on the type of software, but a text editor shouldn’t need those rights.
Do not use hardwired paths, it will just make you and the user miserable when it’s time to move to ‘Windows 56”…
Do offer at least a basic command line interface for your program, makes scripting easier.
Related to the previous point: Do offer a switch for silent installation and parameter(s) to pre-configure the package (e.g.:
/c=config.ini). Very helpful for deploying your software with a package management software like “DSM”.
Do not prepend directory paths or registry keys with your organization name if you’re just a small developer with one well known application; it just makes it harder to find that stuff if it’s hidden under