The problem is not the engine. It’s the Epic Games Launcher that crashes. If you take a look into the log you should see some
[2025.06.12-20.17.13:880][518] LogCommunityPortalAppManager: RequestAppInstall: Add INSTALL action for artifact Hash:PluginName
[2025.06.12-20.17.13:880][518]LogCommunityPortalAppManager: RequestAppInstall: Inserted UNCHANGED action for main game artifact (null):(null):(null) at index 0
[2025.06.12-20.17.13:883][518]LogWindows: Error: appError called: Assertion failed: IsValid() [File:D:\build++Portal\Sync\Engine\Source\Runtime\Core\Public\Templates/SharedPointer.h] [Line: 890]
I think everybody is affected by this since today. Same reports in UE Discord channels as well.
If you go to the install directory of the launcher, there is a Data folder and then a Download Manager folder. Delete the JSON file in that and the launcher should start up again.
Seem like some genius at Epic made a mistake. Every time the JSON at ‘C:\ProgramData\Epic\EpicGamesLauncher\Data\DownloadManager’ is populated with any data, it makes the launcher crash. You don’t even have to delete the file, if you just open it in notepad, remove the content and leave a [ ] - it works as well.
So my guess, there won’t be a way around it until they patch whatever it is that causes it to crash. Just remove the json or change the content to [ ] and wait for an update, I guess.
Cool. Still can’t reinstall a crucial plugin. Guess I just won’t work on anything until Epic fixes their garbage launcher or lets me use a previous version.
what is clear is that the problem is in the download queue, both my solution and the one put above to delete the json, in the end it is the same solution, if it does not let you enter the launcher you have to delete the json, if it lets you enter the launcher for a few minutes, you can cancel the queue from there, anything you are going to install will crash, be it fab plugin, quixel plugin, odyssey, or any other asset, it will crash, right now it is the only solution to be able to be inside the launcher without crash, but to install the plugins or assets without crash there is no solution, it must be something internal to epic games
edit: it only happens in engine plugins, not in other asset types
It’s not really a solution if you need the plugin. As soon you would install it you get crashes again. I bought one a day ago and can’t install it now.
Hey there @HonorDev! Welcome to the community! There was an update pushed to the launcher that was geared towards correcting this issue. Did this correct the issue for you?
Launcher update fixed the issue. I had some error that prevented me to install one plugin at first but after installing another one the first one even installed without issue. So everything looks fine now. Thanks.
