The downloaded file can not be opened as the default launcher of that file is not set to Java. Your antivirus or Microsoft Firewall is blocking the file. Minecraft mods are corrupted.

Minecraft players can modify their gameplay experience in a multitude of ways and across different editions, thanks to Java Edition mods and Bedrock Edition add-ons.

Although Minecraft certainly has its own physics engine built within Java and Bedrock's codebase, some players might like to see a substantial improvement to the engine.

Minecraft: Java Edition is made better with mods, and we have everything you need to know to install and play with mods on Windows PCs.

You can install mods in "Minecraft" by playing the "Java Edition" and using the third-party app Minecraft Forge.

As a free and open-source application for Java edition, there are hardly any reasons not to use Minecraft Forge - many mods even require this mod loader to operate.

4. Back the existing Minecraft.jar for when you want to upgrade back to 1.3.2, then copy and replace the 1.2.5 jar file into the bin folder. Installing legacy versions of Forge Best of Minecraft ...