Flight simulators have evolved. FSX uses different registry hives than Prepar3D v4, v5, or v6. A "bad" REG file might point to the wrong directory, causing your add-on to look for files that don’t exist. The result? Endless "Aircraft not found" errors or CTDs (Crash to Desktop).
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products on computers without an internet connection or when the standard login method fails. Sudeep Audio How to Download the Official FLRegKey Flight simulators have evolved