Download the server and go to java -Xms1G -Xmx8G -jar forge-1.16.5-36.1.2.jar
pause
And changed the name to start.bat
2021-03-27 22:41:02,795 main WARN Advanced terminal features are not available in this environment
[22:41:02] [main/INFO] [cp.mo.mo.Launcher/MODLAUNCHER]: ModLauncher running: args [--gameDir, ., --launchTarget, fmlserver, --fml.forgeVersion, 36.1.2 , --fml.mcpVersion, 20210115.111550, --fml.mcVersion, 1.16.5, --fml.forgeGroup, net.minecraftforge]
[22:41:02] [main/INFO] [cp.mo.mo.Launcher/MODLAUNCHER]: ModLauncher 8.0.9+86+master.3cf110c starting: java version 16 by Oracle Corporation
Exception in thread "main" java.lang.IllegalAccessError: class cpw.mods.modlauncher.SecureJarHandler (in unnamed module @0x534df152) cannot access class sun.security.util.ManifestEntryVerifier (in module java.base) because module java.base does not export sun.security.util to unnamed module @0x534df152
at cpw.mods.modlauncher.SecureJarHandler.lambda$static$1(SecureJarHandler.java:41)
at cpw.mods.modlauncher.api.LamdbaExceptionUtils.uncheck(LamdbaExceptionUtils.java:95)
at cpw.mods.modlauncher.SecureJarHandler.<clinit>(SecureJarHandler.java:41)
at cpw.mods.modlauncher.Launcher.lambda$new$6(Launcher.java:55)
at java.base/java.util.concurrent.ConcurrentHashMap.computeIfAbsent(ConcurrentHashMap.java:1708)
at cpw.mods.modlauncher.api.TypesafeMap.computeIfAbsent(TypesafeMap.java:52)
at cpw.mods.modlauncher.api.TypesafeMap.computeIfAbsent(TypesafeMap.java:47)
at cpw.mods.modlauncher.Environment.computePropertyIfAbsent(Environment.java:62)
at cpw.mods.modlauncher.Launcher.<init>(Launcher.java:55)
at cpw.mods.modlauncher.Launcher.main(Launcher.java:66)
at net.minecraftforge.server.ServerMain$Runner.runLauncher(ServerMain.java:63)
at net.minecraftforge.server.ServerMain$Runner.access$100(ServerMain.java:60)
at net.minecraftforge.server.ServerMain.main(ServerMain.java:57)
An error has occurred