This means you lack
If you use Steam version, Steam needs a few kicks:

• Make sure you have less than 50 subscribed mods. If you have more, unsubscribe from Guardians of Azeroth, then unsubscribe from some other mods and subscribe to Guardians of Azeroth again.
  
• Open the launcher, close it and reopen it.
  
• Unsubscribe, open the launcher, subscribe again, Steam should start downloading.

If you installed it manually, or the solution for Steam version doesn't work somehow, the Manual Download from GitHub[github.com] following the instructions from there might help. MAKE SURE YOU UNZIPPED THE FILE YOU LACKED.

This means you lack
If you use Steam version, Steam needs a few kicks:

• Open the launcher, close it and reopen it.
  
• Unsubscribe, open the launcher, subscribe again, Steam should start downloading.

If you installed it manually, or the solution for Steam version doesn't work somehow, the Manual Download from GitHub[github.com] following the instructions from there might help. MAKE SURE YOU UNZIPPED THE FILE YOU LACKED.

Here we can only list possible problems and their solutions:

• You might be using a not-supported CK2 version. The supported CK2 version is written on all the downloading pages, switch to it.
  
• You might be using other not-compatible mods. Try to disable all the mods except Guardians of Azeroth. Sometimes the launcher may show an active mod as inactive. To make sure they all are disabled, being on the Mods tab in the launcher, check and uncheck the checkbox to the right of the Mods tab. After that, check Warcraft: Guardians of Azeroth on the list.
  
• If you're sure other mods are disabled, your CK2 version may be modified by default. It happens when you do some lewd things right in the game files. To find out if this is the cause, open the launcher and remember the checksum (4 letters written between parentheses in the upper right corner). These letters are the checksum of the current vanilla version. Let's run the game WITHOUT ANY MODS. When you get to the main menu, you will see your game checksum in the bottom left corner. These 2 checksums must be identical. Otherwise, you need to reinstall CK2. I highly recommend finding the former CK2 folder after uninstallation and deleting it. There may be leftover files that will damage your CK2 once again if you install it in the same place.
  
• You might have downloaded corrupted files. In this case, I would recommend doing the Manual Download from GitHub[github.com] following the instructions from there.

Try to disable all the mods except Guardians of Azeroth. If it didn't help, most likely it's a bug and I would ask to Report it on GitHub[github.com].


If you still have problems, write it in the comments, I'll try to come up with solutions.