The most reliable method to fix LS-0013 error in Fortnite is explained step-by-step below.
Step 1: The first thing you need to do is exit the Epic Games launcher from the system tray.
Step 2: And then come up to the File Explorer.
Step 3: After that, you have to go to the C:/ drive.
Step 4: And open up the Program Files.
Step 5: Here, you will find the Epic Games folder, double click on it.
Step 6: And go to the Fortnite folder.
Step 7: Open up the FortniteGames folder.
Step 8: After that, you have to go to the Binaries folder.
Step 9: Double-click on the Win64 folder.
Step 10: Now, you need to find the FortniteClient-Win64-Shipping; scroll down to find it.
Step 11: Now, right-click on FortnightClient-Win64-Shipping and select the Properties option. Come up to the Compatibility section and uncheck “Run this program as an administrator”. Click on Apply then Ok option.
Step 12: Now, you have to repeat these steps with the other two below the FortnightClient-Win64-Shipping, as you can see in the given image.
Step 13: Now, come up to the Epic Games launcher and click on the Library option that appears on the left side.
Step 14: Launch the game, and you are done resolving this issue.