Try deleting the “webcache” folder along with its related subfolders, please:

  1. Press the Windows key + R on your keyboard to open the Run dialog box.
  2. Type %localappdata% and press Enter. This will open up the Local AppData folder.
  3. Find and open the “webcache” folder.
  4. Delete the “webcache” folder as well as its related subfolders, i.e. “webcache_4147” and “webcache_4430”.
  5. Restart your computer and try launching the game again.
If the above doesn't help, try installing the game and the Epic Games launcher on the same hard-drive (e.g. the C: drive), please.