Released in 2008, version 8.5.1 was part of the LabVIEW 8.x series. This generation introduced features like project-style organization and improved debugging tools. The 8.5.1 runtime engine is specifically designed to run applications that were created using LabVIEW version 8.5 or 8.5.1 themselves.
You should use this runtime if a specific application's documentation calls for it. While a version check error message during installation or execution will also point you to the exact LVRTE version required, the key point to remember is that runtime engine versions are generally not forward or backward compatible: . labview runtime engine 85 1 download hot
For any modern use, (free, no LabVIEW needed) – it's backward compatible only to version 2013. Released in 2008, version 8
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