Launcher problems

HMCL Crash Analyzer Error (UnknownFormatConversionException: Conversion = 'D')

What it looks like in the log

java.util.UnknownFormatConversionException: Conversion = 'D'

How to fix it

  1. Update HMCL to version 3.5.3.230 or newer, where this translation formatting bug was fixed.
  2. If the built-in launcher updater only offers an older stable build, switch to the Development update channel in HMCL settings or download the latest release directly from the official HMCL-dev/HMCL GitHub Releases page.
  3. Once HMCL is updated, launch the game again or check your '.minecraft/crash-reports' folder directly to read the actual underlying Minecraft crash report.
LoadersVanilla, Forge, Neoforge, Fabric, Quilt
SeverityBreaks something
CategoryLauncher problems

Check your own log

Related errors

Launcher problemsATLauncher AccessDeniedException When Deleting temp/natives FolderDo not troubleshoot this AccessDeniedException directly; scroll up in the ATLauncher console above the 'Oh no.Launcher problemsClassNotFoundException: net.minecraft.launchwrapper.LaunchConnect to the internet and launch the game in Online Mode at least once so your launcher can download missingLauncher problemsFound Multiple Arguments for Option launchTarget (Duplicate Forge Launch Arguments)If you store worlds or mods inside the version folder, back up your `saves`, `mods`, `config`, and `resourcepaLauncher problemsHMCL Crash: NoClassDefFoundError in DefaultGameLauncher$$LambdaForce-close the frozen HMCL process using Windows Task Manager or your system's process manager.Launcher problemsHMCL Launcher Error: SAXParseException in Log4jHandlerUpdate Hello Minecraft! Launcher (HMCL) to version 3.x (or at least 2.7.8.45+) from the official HMCL website Launcher problemsMissing Log4j Library on Launch (LogManager ClassNotFoundException)Launch a clean Vanilla profile of the exact same Minecraft version once before starting your modded profile so