All of the following criteria must be met

• All Requirements must be installed.
• Changed the title so that it doesn't just says "[Bug]: "
• I have searched the GitHub issues for my bug, even in the closed issues.

All of the following are optional to answer

• Tried reinstalling the Game.
• Tried reinstalling MelonLoader.
• Tried restarting PC.
• Was able to see the Start Screen.

Describe the issue.

So I had Melon installed with BTD6 along with the Mod Helper, but the mod button wasn't appearing in game/ Uninstalled both and went to reinstall, but when I tried to add Melonloader back it tells me INTERNAL FAILURE! Please upload the log file "C:\Users\user\Downloads\MLInstaller_24-6-26-03-51-05-05.774.log" when requesting support
If it makes any difference I used the automatic install, since my antivirus blocked the manual install

Did you attach your log file?

No, I could not find a log file at {Game_Directory}\MelonLoader\Latest.log