Affects Version/s: 2.1.16102
Fix Version/s: None
Component/s: Minecraft Launcher
Environment:Windows 10; Version 2004; Build 19041.450;
The Minecraft Launcher is using an incorrect method of resolving domains by bypassing the preferred DNS resolver on Windows.
I suspect this to be an issue with outbound port 53 blocked on a router level in order to force an internal DNS service to be used. The router accepts port 53 and performs lookups on the router. This internal DNS on the router is capable of resolving external domains such as mojang.com. I simply don't want DNS Leaks which is why it's blocked externally. I may also mention, this is also the only program I have run into DNS resolving issues.
The Windows environment is specified below. This was performed on a clean install of Windows and using the "Minecraft.exe" alternative install found on https://www.minecraft.net/en-us/download/alternative/. This was launched from the directory C:\Users\Thomas\Downloads\mc\.
The Minecraft Launcher errors after a few seconds since launching the executable. Two error messages appear one after each other:
- Couldn't load launcher core from C:\Users\Thomas\Downloads\mc\game\launcher.dll: LoadErrorNotPresent
- Unable to start the Minecraft Runtime Environment. This is most likely caused by a corruption. Please try to reinstall Minecraft.
Checking the launcher_log.txt file (attached), the error can be quickly traced:
[Error: 2020-08-21 00:11:10.4186235: NetQueue.cpp(471)] NetQueue: No ip address available. Error code 6, Host: launchermeta.mojang.com
[Info: 2020-08-21 00:11:10.4186812: NetQueue.cpp(506)] NetQueue: Action failed with result "Could not resolve: launchermeta.mojang.com (Timeout while contacting DNS servers)" (6) : https://launchermeta.mojang.com/v1/products/launcher/d03cf0cf95cce259fa9ea3ab54b65bd28bb0ae82/windows-x86.json
The domain launchermeta.mojang.com can be resolved within a second using my browser and even nslookup,
Address: fd00::9:e803Non-authoritative answer:
Furthermore, the windows-x86.json on the same system's browser from the link mentioned in the log loads as expected with valid JSON. Clearly, this is an issue with the Minecraft Launcher resolving the launchermeta.mojang.com domain. Further investigation will show that the launcher fails to resolve any domain name.
A work around is using the host file to bind a domain name to its IP address. Previously, the host file was empty.
Since the previous nslookup resolved launchermeta.mojang.com as 126.96.36.199, this was then added to the hosts file:
Relaunching allowed the launchermeta.mojang.com to be resolved and as a result, windows-x86.json to be fetched. A new window appeared, but without any moving progress. This is screenshot Updating Minecraft Launcher No Progress where the progress bar remained at ~5%.
After cancelling the download, I then checked the launcher_log.txt and found that the file windows-x86.json did in fact download successfully,
[Info: 2020-08-21 00:37:38.6801885: NetQueue.cpp(603)] NetQueue: Starting net action https://launchermeta.mojang.com/v1/products/launcher/d03cf0cf95cce259fa9ea3ab54b65bd28bb0ae82/windows-x86.json
[Info: 2020-08-21 00:37:38.8277587: NetQueue.cpp(474)] NetQueue: Primary ip: 188.8.131.52, Host: launchermeta.mojang.com
[Info: 2020-08-21 00:37:38.8278007: NetQueue.cpp(541)] NetQueue: Action finished: https://launchermeta.mojang.com/v1/products/launcher/d03cf0cf95cce259fa9ea3ab54b65bd28bb0ae82/windows-x86.json
[Info: 2020-08-21 00:37:38.8278178: NetQueue.cpp(562)] NetQueue: Action finalized: https://launchermeta.mojang.com/v1/products/launcher/d03cf0cf95cce259fa9ea3ab54b65bd28bb0ae82/windows-x86.json
However, another domain still had issues being resolved,
[Error: 2020-08-21 00:38:39.0164035: NetQueue.cpp(471)] NetQueue: No ip address available. Error code 6, Host: launcher.mojang.com
The same thing was done as before, using nslookup to resolve launcher.mojang.com and then added that manually to the host file. I did this repeatedly until I was finally able to launch Minecraft.
Below are screenshots that mention issues that other people have run into and reported - which may be directly linked to this issue.
Even with the correct credentials, the message, "Sorry! Make sure you are online and try again" appears. The log mentions a failure to resolve authserver.mojang.com.
Check screenshot "Minecraft Launcher - Login Issue".
After logging in and attempting to download the game, the download hangs halfway without continuing. This is a result of libraries.minecraft.net and resources.download.minecraft.net not being resolved within the launcher.
Check screenshot "Minecraft Launcher - Download Hangs".
After adding the previously mentioned domains to the host file; the launcher was able to authenticate my account credentials, download, and run Minecraft.
My host file ended up looking like,
I should mention that anyone trying to use this as a fix may need to resolve the domains above with nslookup in the event that the IPs have changed for the domains.