Error: GTA V was not automatically detected. This error means that the multiplayer cannot detect where you have the game files. 
If you are playing through the Rage MP, you only need to do three things:

  1. Launch RAGE:MP and go to the settings section.
  2. Find the “Game Location” section and click “Change Location”.
  3. Specify the path to your GTA 5 folder.
RAGE:MP
RAGE:MP

Error: GTA V was not automatically detected. If you play through the Grand Launcher, you need to do four things:

  1. Right-click the Grand Launcher shortcut.
  2. Select the “Properties” section.
  3. Open the file location section and select the folder with RAGE:MP.
  4. Open the UpDater file (update tool).
Launcher properties, location
Launcher properties, location 2
Launcher properties, location

All you have to do is go into the game, the main thing is not to mix up and do not accidentally go to GTA Online.

You have successfully fixed the RAGE MP error. Congratulations!

Dear friend, now you know how to fix this mistake. By the way, we have a video on our channel in which we presented all the information, so I advise you to watch it!