Repair procedure RP–02 Installation isolation
Run an older Java Edition version safely
The official launcher path
- 01Open the Minecraft Launcher and pick Installations.
- 02Choose New installation.
- 03In the Version dropdown, select the release you want. Tick “historical versions” in launcher settings if old releases are hidden.
- 04Give the installation its own game directory if you want its saves and options isolated — recommended when hopping eras.
- 05Save, select the installation on the Play tab, and start it once to let the launcher fetch that version’s files.
No third-party launcher, jar swap, or downloaded client is required for stock versions, and this site will never point you at one.
Evidence boundary Per-release attribution required
JVM requirements are omitted
OlderCraft does not assign JVM versions to historical releases because the current source record does not attribute those requirements release by release. For a standalone server, use the installation documentation published by the exact server distribution and release you intend to run.
Final check / fit
Check the target before switching
Joining a specific server? Confirm its version expectation first — the workbench tells you whether two recorded versions even shake hands, and theserver-side guide explains when a bridge exists.