Since Altium Designer typically requires an internet connection to access the Altium Live Vault, an offline installation is necessary for secure/air-gapped computers or corporate networks with restricted internet access.
Restart Altium Designer.
Once the package is on your target machine, you must redirect Altium Designer to use this local folder instead of the internet. altium extension offline install
The team shipped the board on schedule—and in the project postmortem, the offline-install checklist became a required artifact for future external extensions, stopping the next emergency from turning into a fire drill. altium extension offline install
Tips and Best Practices
| Pros | Cons |
| :--- | :--- |
| Essential Functionality: It allows secure environments to use the software. | Discovery Issue: Altium does not provide a clean repository to download offline extension files directly. |
| Single File Imports: Installing simple plugins (like specific Import/Export translators) via .zip is quick and painless. | Dependency Hell: Complex extensions (like Manufacturer Part Search) often break or require manual folder manipulation to work offline. |
| Version Control: Allows admins to lock specific versions of extensions without auto-updates. | UI Hostility: The interface constantly nags for connection, and the "Install from file" option is buried in a hamburger menu. | altium extension offline install
AltiumInstaller.exe --download-extension "Altium.PcbDesign" --output-dir D:\AltiumOfflineRepo
Because Altium Designer typically retrieves extensions from the Altium Cloud, you must first download a complete offline set from a computer with internet access.