Having big problem with forge after internet went out

[Nuggie___]

My GF and I both downloaded 44.1.17 so we could use OptiFine 1.19.3 pre5. We're using Hamachi so she can connect to my world, before downloading Forge we had no issue's with anything, Forge was working fine until her internet cut out but now she's just having problems we can't fix, she's lost her character (inventory, achievements , can't view anyone's skin while forge is active and she's finding she's getting sent back to World spawn). She has uninstalled and reinstalled everything, there shouldn't be a possibility of a file being corrupted, She's also being logged out of her account and needs to log back in every time she needs to launch. I on the other hand don't have a single problem so I really don't know what the problem is with hers.  

[ChampionAsh5357]

Please provide the debug.log from the logs folder within the game directory of the erroring account via a pastebin or gist.

[Nuggie___]

Is that still going to show all the information required after deleting and reinstalling the game and everything else ? 

 

[Nuggie___]

15 minutes ago, ChampionAsh5357 said:

Please provide the debug.log from the logs folder within the game directory of the erroring account via a pastebin or gist.

https://gist.github.com/OwOssyUwU/895f71211464b4f5c140d3e2e3aecb1e

[ChampionAsh5357]

4 hours ago, Nuggie___ said:

Is that still going to show all the information required after deleting and reinstalling the game and everything else ? 

Yes, there should be no issue.

3 hours ago, Nuggie___ said:

https://gist.github.com/OwOssyUwU/895f71211464b4f5c140d3e2e3aecb1e

It seems as though their account failed to authenticate so they are playing in offline mode. Would you mind asking them to disable their ipv6 traffic on their machine? You can lookup on the internet how to do so.

[Pocket]

Hey there, I'm the person with the issues. I disabled ipv6 traffic and skins are visible again so I don't think I'm having issues with offline mode anymore. I spawned at world spawn with no items but that would be because he deleted my save file I'm sure. Are you able to tell me why ipv6 being enabled wasn't an issue before and if I'll ever be able to enable it again without issues? I hear there's window's processes that rely on it.

[JoJoao_Agiota]

5 hours ago, ChampionAsh5357 said:

Yes, there should be no issue.

It seems as though their account failed to authenticate so they are playing in offline mode. Would you mind asking them to disable their ipv6 traffic on their machine? You can lookup on the internet how to do so.

I had the same problem, I disabled the IPV6 protocol and now the account is authenticating again using Forge, my skin showed again and I was able to enter my dedicated server. Thanks!

PS. For those who don't want to disable the IPV6 protocol you can use the argument in the launcher:
-Djava.net.preferIPv4Stack=true

[ChampionAsh5357]

2 hours ago, Pocket said:

Are you able to tell me why ipv6 being enabled wasn't an issue before and if I'll ever be able to enable it again without issues? I hear there's window's processes that rely on it.

Basically, Forge added full support for ipv6 traffic for Minecraft online. If ipv6 isn't being used in both directions to send and receive traffic (which is typically the case with these issues), it will likely result in a connection timeout as the connections are not always compatible with each other. Preferably, you don't want to disable ipv6 to take advantage of all the features that are supported for it, but afaik, the only windows applications that may be affected would be the mail app and probably any remote program designed by microsoft, so it wouldn't affect a good number of people.

Jojo's solution is probably a good workaround for this, so I'll make a mental note for the future to use it.

[Nuggie___]

she did the ipv6 thing and it all works properly now, thank you so much 

 

[Paint_Ninja]

I've written a fairly comprehensive troubleshooting guide that goes over solutions for the root cause of this issue here. IPv6 support was added because when it works, it usually decreases your ping time as you have a more direct connection to the server with less intermediary processing through NAT hops. As such, disabling IPv6 should be treated as a last resort solution as it'll likely increase your ping time to capable servers, increase lag and break some Vanilla networking features such as connecting to IPv6-only servers.