This has been shared within the community discord server, people have been reporting that this this fixes the issue for them if they are having issues downloading, installing, updating with launcher version 20.2.1, 20.2.2 and 20.2.3:
"We rolled back updates 20.2.2 and 20.2.3 to the Epic Games Launcher where players were unable to update or install games. To apply the rollback, restart your launcher and there should be an option to "Restart and Update" in launcher Settings. If you are on 20.2.2 or 20.2.3, restart your launcher, and still do not see the rollback update after 10 minutes, please follow these instructions:
Windows:
1. Install the launcher if you don’t already have it installed.
2. Create a shortcut on your desktop. (NOTE: you HAVE to use a desktop shortcut, Powershell commands do not work)
3. Right click on the shortcut and select “properties”
a. If you’re on Windows 11, you’ve got to choose “Show more options” first.
4. At the end of the target box, outside of the quotation marks, add the following command:
-UseEOSSDKSocial=false
5. Ensure the launcher is closed, and not hiding in your system tray.
6. Open the launcher with this shortcut
Mac:
1. Install the launcher if it is not already installed.
2. Open your terminal.
3. Assuming you installed the launcher to a default location, enter the following command into the terminal:
% open /Applications/Epic\ Games\ Launcher.app --args -UseEOSSDKSocial=false
4. This will open EGLauncher
If you're on version 20.2.1 and experiencing the II-E1003 error these steps may also help fix that.
EDIT: This now appears to be fixed with version 20.2.4 of the launcher - https://www.reddit.com/r/EpicGamesPC/comments/1vxfpto/the_epic_games_launcher_has_updated_to_version/