Locate launcher_profiles.json and delete it (or move it to your desktop as a backup).
If it works, add Minecraft.exe and the .minecraft folder as exceptions in your security software. 6. Delete the "Launcher_Profiles.json" failed to download version manifest cannot find jar url
The "Version Manifest" is a JSON file that tells the launcher exactly where the game files (JARs) are located on the web. When the launcher says it "cannot find JAR URL," it means the communication line is cut—either by a local software conflict, a network block, or an outdated launcher trying to ping a retired server address. Locate launcher_profiles
In 90% of cases, simply deleting the corrupted version folder (Fix #1) solves the problem immediately. Happy gaming Delete the "Launcher_Profiles
If you are using a third-party launcher (like ATLauncher, Twitch/CurseForge, or GDLauncher), this is the most likely solution.
If you are using the old Windows 7/8 launcher, it may struggle with modern URL redirects.