Try this:
- Delete your user files. For deleting your user files, you have to:
a. Make sure that your Steam Cloud is disabled in Steam, AoE2 game, Properties, General.
b. Go to C:\Users\YOUR_USER\Games\Age of Empires 2 DE.
c. Copy your user folder to a safe place, it has lots of numbers.
d. Delete the original folder
e. Verify your files in Steam, AoE2 game, Properties, Local Files.
f. Open the game again. A new user folder will be created.
If this works, then copy back the files from your old user folder. These files are in this folder -C:\Users\YOUR_USER\Games\Age of Empires 2 DE<0>\Savegame, Recorded Games and Save games.