Complete Guide: Code Signing EXE, DLL, and MSI Files
Apr 5, 2026 · Tutorials · 6 views
Windows SmartScreen warns users when they download unsigned software. Code signing eliminates these warnings and builds trust with your users.
What is Code Signing?
Code signing applies a digital signature to Windows executables (EXE, DLL, MSI, SYS). It proves:
- Identity — The software comes from a verified publisher
- Integrity — The file hasn't been modified since signing
- Timestamp — The signature remains valid even after the certificate expires
Why Automate Code Signing?
In modern CI/CD pipelines, builds happen multiple times per day. Manual code signing creates a bottleneck. OneSigner automates this:
- Your CI pipeline builds the EXE/DLL/MSI
- Pipeline uploads to OneSigner via REST API
- OneSigner signs with your EV code signing certificate
- Pipeline retrieves the signed binary
EV vs. Standard Code Signing
| Feature | Standard | EV (Extended Validation) |
|---|---|---|
| SmartScreen warnings | Reduced over time | Immediate trust |
| Private key storage | Software or hardware | Hardware only (USB token) |
| Price | ~$200/year | ~$400/year |
| Identity verification | Domain + organization | Extended business verification |
OneSigner supports both, but we recommend EV certificates for the best user experience.
Getting Started
See our Code Signing Setup Guide for step-by-step instructions.