Look in your Windows Defender or antivirus history.
If you own the game on , you can right-click RimWorld > Properties > Betas and select version-1.4.3901 from the dropdown to get a complete, verified copy. RimWorld.v1.4.3580.zip
If the .zip file is missing a "piece" to make it run (like a .dll or the RimWorldWin64.exe ), it’s usually because an antivirus program flagged and quarantined it. Look in your Windows Defender or antivirus history
Unless you need that exact build for a specific mod compatibility, the final stable version of 1.4 is . Unless you need that exact build for a
Since v1.4.3580 is an older sub-version of the 1.4 "Biotech" era, most mods labeled for should work. However, if you are looking for a specific "piece" of content: Steam Workshop: You can filter by version 1.4.
A working RimWorld folder should contain RimWorldWin64_Data , MonoBleedingEdge , and the executable. 2. Version-Specific Mods
Here are the most common things people look for with specific RimWorld versions: 1. Missing Executable or Runtime Files