- me.exe for extracting and embedding manifests from/in assemblies
- IIS7 doesn't have a metabase, so installers which try and use it will fail.
- The local admin account on Windows Server 2008 has UAC disabled.
- Don't create programs to manipulate configuration files, create MMC Snap-ins.
Regarding Smart Client development:
- When adding new functionality (such as WPF elements) interop with existing code, don't rewrite.
- Build an ecosystem through extensibility (X-ref this post from coding horror.)
- Embrace the Software plus Services model for occasionally connected apps.
- Integrate with Office, where possible, rather than make a completely new app.