I created a tutorial based on @Farzad_Bagheri solution. Hopefully it is clear enough for people to solve the issue.
Hey @herberthippo and everyone!
Thank you for your patience while we investigated reports of Fab failing to launch. We’ve identified that this can be caused by stale or orphaned install records left behind in Epic’s local manifest data, which can interfere with Fab’s launch process.
We’ve put together a manual fix. Here’s how to use it:
Before you start:
- Fully close the Epic Games Launcher and Fab, including any background processes (check Task Manager to confirm nothing named “EpicGamesLauncher” or “Fab” is still running).
- We recommend backing up any files the script identifies before deleting them, just in case.
Step 1 - Run the diagnostic script
Open PowerShell (not Command Prompt) and paste in the following command:
$pd=if($env:ProgramData){$env:ProgramData}else{'C:\ProgramData'};$ii=Join-Path $pd 'Epic\EpicOnlineServicesShared\InstallHelper\InstalledItems';$lm=Join-Path $pd 'Epic\EpicGamesLauncher\Data\Manifests';$G=@{};$add={param($d,$f,$e)if([string]::IsNullOrWhiteSpace($d)){return};$k=$d.TrimEnd('\').ToLowerInvariant();if(-not $G[$k]){$G[$k]=[pscustomobject]@{Dir=$d;Files=@();Exes=@()}};$G[$k].Files+=$f;if($e){$G[$k].Exes+=[string]$e}};if(Test-Path -LiteralPath $ii){Get-ChildItem -LiteralPath $ii -Filter *.egi -ErrorAction SilentlyContinue|%{try{$r=(((Get-Content -LiteralPath $_.FullName -Raw|ConvertFrom-Json).PSObject.Properties)|Select-Object -First 1).Value}catch{return};if($r.state -eq 'Installed'){& $add $r.dir $_.FullName $r.manifestData.launchExe}}};if(Test-Path -LiteralPath $lm){$fl=@(Get-ChildItem -LiteralPath $lm -Filter *.item -ErrorAction SilentlyContinue);$pdir=Join-Path $lm 'Pending';if(Test-Path -LiteralPath $pdir){$fl+=@(Get-ChildItem -LiteralPath $pdir -Filter *.item -ErrorAction SilentlyContinue)};$fl|%{try{$d=Get-Content -LiteralPath $_.FullName -Raw|ConvertFrom-Json}catch{return};& $add $d.InstallLocation $_.FullName $d.LaunchExecutable}};foreach($k in $G.Keys){$o=$G[$k];$inst=$false;if(Test-Path -LiteralPath $o.Dir){foreach($e in $o.Exes){if($e -and (Test-Path -LiteralPath (Join-Path $o.Dir ($e -replace '/','\')))){$inst=$true}};if(-not $inst -and (Test-Path -LiteralPath (Join-Path $o.Dir '.egstore'))){if(Get-ChildItem -LiteralPath (Join-Path $o.Dir '.egstore') -Filter *.manifest -File -ErrorAction SilentlyContinue|Select-Object -First 1){$inst=$true}}};if($inst){continue};$o.Files|%{$_}}
This will output a list of file paths (if any) that correspond to stale, orphaned install records.
Step 2 - Delete the listed files
If the script returns one or more file paths, manually delete each file listed. If it returns nothing, this particular fix doesn’t apply to your setup, please let us know in this thread so we can look into other causes.
Step 3 - Relaunch
Restart the Epic Games Launcher and try launching Fab again.
I gave this a try but the issue still remains for me.
When I ran the command, I had a lot of files that came up that I removed. I made sure the launcher was completely closed before doing so. I relaunched the launcher and the plugins were not initially installed. I tried to install Fab from the epic launcher but it didn’t appear to do anything (nothing showed in the downloads) then after a short while both Bridge and Fab showed as installed, however, they are not within the plugins folder and not available when I launch a project. When I try to remove them I get that same error message of update failed/installed failed
I ran the powershell command again and no files came up this time
Gave my pc a restart - no luck
I then tried verifying the 5.8 install
After verifying, still no luck and I ran the command again and no files show
Might just try a complete re-install of UE5.8 and the launcher next unless there is anything else I could try.