Can't connect to local server despite using same mods

[bitter6290]

Hello,

I'm using Forge version 36.2.34 for Minecraft 1.16.5. I'm unable to join a local server, despite using all of the same mods. When I try to join, these lines are repeated several times in the console, followed by a generic "Disconnected" message in-game.

[09:45:31] [Netty Client IO #0/ERROR]: Channels [theabyss:theabyss,blue_skies:main,structure_gel:main,cfm:network,chiseled:chiseled,shrines:main_channel,environmental:play,colony4cc:main,autoreglib:main,endergetic:net,upgrade_aquatic:net,chiselsandbits:chiselsandbits,immersiveengineering:main,cosmeticarmorreworked:main,botania:chan,slimy_stuff:slimy_stuff,pyromancer:pyromancer,create_stuff_additions:create_stuff_additions,personality:net,abnormals_core:net,polymorph:main,skyvillages:skyvillages,minecolonies:net-channel,quark:main,artifacts:main,vampirism:main,akashictome:main,teamlapenlib:main,buildinggadgets:main,computercraft:network,pixelmoninformation:network,flywheel:network,constructionwand:main,create:network,dummmmmmy:dummychannel,mekanism:mekanism,terraincognita:channel,stalwart_dungeons:stalwart_dungeons,createaddition:main,environmental:login,mekanismgenerators:mekanismgenerators,nethers_exoticism:nethers_exoticism,storagedrawers:main_channel,securitycraft:securitycraft,adhooks:main,psi:main,psipherals:main,create_confectionery:create_confectionery,curios:main,thebeginning:thebeginning,forgeendertech:main,castle_in_the_sky:main,structurize:net-channel,mana-and-artifice:main,patchouli:main,pneumaticcraft:main_channel,chisel:main,trashcans:main,ironchest:network,geckolib3:main,the_idle:the_idle,twilightforest:channel] rejected vanilla connections
[09:45:31] [Netty Client IO #0/ERROR]: Channels [theabyss:theabyss,blue_skies:main,structure_gel:main,cfm:network,chiseled:chiseled,shrines:main_channel,environmental:play,colony4cc:main,autoreglib:main,endergetic:net,upgrade_aquatic:net,chiselsandbits:chiselsandbits,immersiveengineering:main,cosmeticarmorreworked:main,botania:chan,slimy_stuff:slimy_stuff,pyromancer:pyromancer,create_stuff_additions:create_stuff_additions,personality:net,abnormals_core:net,polymorph:main,skyvillages:skyvillages,minecolonies:net-channel,quark:main,artifacts:main,vampirism:main,akashictome:main,teamlapenlib:main,buildinggadgets:main,computercraft:network,pixelmoninformation:network,flywheel:network,constructionwand:main,create:network,dummmmmmy:dummychannel,mekanism:mekanism,terraincognita:channel,stalwart_dungeons:stalwart_dungeons,createaddition:main,environmental:login,mekanismgenerators:mekanismgenerators,nethers_exoticism:nethers_exoticism,storagedrawers:main_channel,securitycraft:securitycraft,adhooks:main,psi:main,psipherals:main,create_confectionery:create_confectionery,curios:main,thebeginning:thebeginning,forgeendertech:main,castle_in_the_sky:main,structurize:net-channel,mana-and-artifice:main,patchouli:main,pneumaticcraft:main_channel,chisel:main,trashcans:main,ironchest:network,geckolib3:main,the_idle:the_idle,twilightforest:channel] rejected vanilla connections
[09:45:31] [Netty Client IO #0/ERROR]: Channels [theabyss:theabyss,blue_skies:main,structure_gel:main,cfm:network,chiseled:chiseled,shrines:main_channel,environmental:play,colony4cc:main,autoreglib:main,endergetic:net,upgrade_aquatic:net,chiselsandbits:chiselsandbits,immersiveengineering:main,cosmeticarmorreworked:main,botania:chan,slimy_stuff:slimy_stuff,pyromancer:pyromancer,create_stuff_additions:create_stuff_additions,personality:net,abnormals_core:net,polymorph:main,skyvillages:skyvillages,minecolonies:net-channel,quark:main,artifacts:main,vampirism:main,akashictome:main,teamlapenlib:main,buildinggadgets:main,computercraft:network,pixelmoninformation:network,flywheel:network,constructionwand:main,create:network,dummmmmmy:dummychannel,mekanism:mekanism,terraincognita:channel,stalwart_dungeons:stalwart_dungeons,createaddition:main,environmental:login,mekanismgenerators:mekanismgenerators,nethers_exoticism:nethers_exoticism,storagedrawers:main_channel,securitycraft:securitycraft,adhooks:main,psi:main,psipherals:main,create_confectionery:create_confectionery,curios:main,thebeginning:thebeginning,forgeendertech:main,castle_in_the_sky:main,structurize:net-channel,mana-and-artifice:main,patchouli:main,pneumaticcraft:main_channel,chisel:main,trashcans:main,ironchest:network,geckolib3:main,the_idle:the_idle,twilightforest:channel] rejected vanilla connections
[09:45:31] [Netty Client IO #0/ERROR]: Channels [theabyss:theabyss,blue_skies:main,structure_gel:main,cfm:network,chiseled:chiseled,shrines:main_channel,environmental:play,colony4cc:main,autoreglib:main,endergetic:net,upgrade_aquatic:net,chiselsandbits:chiselsandbits,immersiveengineering:main,cosmeticarmorreworked:main,botania:chan,slimy_stuff:slimy_stuff,pyromancer:pyromancer,create_stuff_additions:create_stuff_additions,personality:net,abnormals_core:net,polymorph:main,skyvillages:skyvillages,minecolonies:net-channel,quark:main,artifacts:main,vampirism:main,akashictome:main,teamlapenlib:main,buildinggadgets:main,computercraft:network,pixelmoninformation:network,flywheel:network,constructionwand:main,create:network,dummmmmmy:dummychannel,mekanism:mekanism,terraincognita:channel,stalwart_dungeons:stalwart_dungeons,createaddition:main,environmental:login,mekanismgenerators:mekanismgenerators,nethers_exoticism:nethers_exoticism,storagedrawers:main_channel,securitycraft:securitycraft,adhooks:main,psi:main,psipherals:main,create_confectionery:create_confectionery,curios:main,thebeginning:thebeginning,forgeendertech:main,castle_in_the_sky:main,structurize:net-channel,mana-and-artifice:main,patchouli:main,pneumaticcraft:main_channel,chisel:main,trashcans:main,ironchest:network,geckolib3:main,the_idle:the_idle,twilightforest:channel] rejected vanilla connections
[09:45:32] [Netty Client IO #9/ERROR]: Channels [theabyss:theabyss,blue_skies:main,structure_gel:main,cfm:network,chiseled:chiseled,shrines:main_channel,environmental:play,colony4cc:main,autoreglib:main,endergetic:net,upgrade_aquatic:net,chiselsandbits:chiselsandbits,immersiveengineering:main,cosmeticarmorreworked:main,botania:chan,slimy_stuff:slimy_stuff,pyromancer:pyromancer,create_stuff_additions:create_stuff_additions,personality:net,abnormals_core:net,polymorph:main,skyvillages:skyvillages,minecolonies:net-channel,quark:main,artifacts:main,vampirism:main,akashictome:main,teamlapenlib:main,buildinggadgets:main,computercraft:network,pixelmoninformation:network,flywheel:network,constructionwand:main,create:network,dummmmmmy:dummychannel,mekanism:mekanism,terraincognita:channel,stalwart_dungeons:stalwart_dungeons,createaddition:main,environmental:login,mekanismgenerators:mekanismgenerators,nethers_exoticism:nethers_exoticism,storagedrawers:main_channel,securitycraft:securitycraft,adhooks:main,psi:main,psipherals:main,create_confectionery:create_confectionery,curios:main,thebeginning:thebeginning,forgeendertech:main,castle_in_the_sky:main,structurize:net-channel,mana-and-artifice:main,patchouli:main,pneumaticcraft:main_channel,chisel:main,trashcans:main,ironchest:network,geckolib3:main,the_idle:the_idle,twilightforest:channel] rejected vanilla connections

I don't know the exact meaning of these lines, but it looks to me like Forge detects a mismatch between my mods and the servers'. However, there is no such mismatch; we're using the same version of Forge and the same list of mods. Is this a known issue with any particular mod? I'm using Optifine; is this a known side-effect of the mod? For what it's worth, I'm also getting a constant stream of

Quote

/config/dsurround/environs-client.toml is not correct. Correcting

messages while the game is open.

Edited August 17, 2022 by bitter6290