diff --git a/Minecraft.Client/Common/Postbuilds/Orbis-postbuild.ps1 b/Minecraft.Client/Common/Postbuilds/Orbis-postbuild.ps1
index 057864de..3b9aed05 100644
--- a/Minecraft.Client/Common/Postbuilds/Orbis-postbuild.ps1
+++ b/Minecraft.Client/Common/Postbuilds/Orbis-postbuild.ps1
@@ -127,7 +127,12 @@ if (-not (Test-Path $genGp4)) {
     Write-Host "Orbis Postbuild: '$pkgSrc' not found, skipping PKG creation."
 } else {
     Write-Host "Orbis Postbuild: Generating GP4..."
-    & $genGp4 $pkgSrc
+    $proc = Start-Process -FilePath $genGp4 -ArgumentList $pkgSrc `
+    -NoNewWindow -Wait -PassThru
+    if ($proc.ExitCode -ne 0) {
+        Write-Host "Orbis Postbuild ERROR: gengp4_app.exe failed with exit code $($proc.ExitCode)"
+        return
+    }
 
     if (-not (Test-Path $gp4File)) {
         Write-Host "Orbis Postbuild ERROR: $gp4File was not created"