One of the less visible but surprisingly common issues molecular modelers face with SAMSON is a SAMSON Extension that refuses to load. Everything seems right — the Extension is installed, SAMSON is up and running — yet nothing happens. If you’ve encountered this, there’s a good chance it’s not your fault. The culprit is often version incompatibility between SAMSON and the Software Development Kit (SDK) used to build the Extension.
Here’s what’s really going on — and how to fix it easily once you understand what’s under the hood.
Understanding SAMSON Extension Compatibility
When SAMSON starts up, it checks if the version of the SDK used to build each installed Extension is compatible with SAMSON’s own SDK version. This compatibility depends on two things:
- The major version of the SDK must match exactly.
- The minor version of the SDK must be less than SAMSON’s minor version.
This means that if your Extension was built with SDK version 1.5.2 and your SAMSON installation is at 1.7.8, all is good: the major version (1) matches, and 5 < 7. But if the Extension was built with SDK 1.8.5, SAMSON 1.7.8 will not load it — the minor version is too high. This protects you from rare bugs caused by calling SDK features that didn’t exist yet in your version of SAMSON.
How to Prevent and Solve Compatibility Issues
1. Keep SAMSON Updated
Most of the time, simply allowing SAMSON to update automatically solves Extension issues. SAMSON looks for newer versions of installed Extensions on SAMSON Connect and updates them when it finds compatible ones.
2. Use the SDK version appropriate for your SAMSON version
If you are developing Extensions, make sure to build them using the SDK version equal to or below your target SAMSON’s SDK minor version. For example, if your users are on SAMSON 9.0.0, don’t build with SDK 9.1.0. Instead, stick to 9.0.X.
3. Know What Happens If You Don’t Update
If a developer releases a new version of an Extension built with SDK 2.0.0, but the user remains on SAMSON 1.7.8, SAMSON won’t upgrade the Extension. The existing version (e.g., 1.6.4) remains installed and functional — but won’t receive new features or fixes.
Why It Matters
For molecular modelers, SAMSON Extensions are critical — from simulation tools to visualization modules. When Extensions stop working due to version mismatches, it interrupts workflows and slows research. Understanding the simple versioning logic helps avoid incompatible combinations and keeps your Extensions running as expected.
For developers, being mindful of compatibility means your Extensions can reach more users, more reliably. For users, staying updated minimizes surprises and maximizes functionality.
To learn more details about SAMSON’s versioning system and compatibility rules, check the full documentation here: https://documentation.samson-connect.net/users/latest/versioning/
SAMSON and all SAMSON Extensions are free for non-commercial use. You can get SAMSON at https://www.samson-connect.net.