diff --git a/Kernel/Modules/Installer.pm b/Kernel/Modules/Installer.pm
index f1c20957e1..b3d37ecb16 100644
--- a/Kernel/Modules/Installer.pm
+++ b/Kernel/Modules/Installer.pm
@@ -1154,8 +1154,9 @@ sub ConnectToDB {
         );
     }
 
+    # Connect to the database without logging errors, as they are already shown to the user.
     my $DBH = DBI->connect(
-        $Param{DSN}, $Param{DBUser}, $Param{DBPassword},
+        $Param{DSN}, $Param{DBUser}, $Param{DBPassword}, { PrintError => 0 }
     );
 
     if ( !$DBH ) {
diff --git a/Kernel/Output/HTML/Layout.pm b/Kernel/Output/HTML/Layout.pm
index 3de1d2ffcc..be65b927da 100644
--- a/Kernel/Output/HTML/Layout.pm
+++ b/Kernel/Output/HTML/Layout.pm
@@ -1310,7 +1310,9 @@ sub Header {
 
     # Generate the minified CSS and JavaScript files and the tags referencing them (see LayoutLoader)
     $Self->LoaderCreateAgentCSSCalls();
-    $Self->LoaderCreateDynamicCSS();
+    if ( !$Self->{InstallerOnly} ) {
+        $Self->LoaderCreateDynamicCSS();
+    }
 
     my %AgentLogo;
 
@@ -1758,10 +1760,14 @@ sub Footer {
     }
 
     # Set an array with pending states.
-    my @PendingStateIDs = $Kernel::OM->Get('Kernel::System::State')->StateGetStatesByType(
-        StateType => [ 'pending reminder', 'pending auto' ],
-        Result    => 'ID',
-    );
+    my @PendingStateIDs;
+
+    if ( !$Self->{InstallerOnly} ) {
+        @PendingStateIDs = $Kernel::OM->Get('Kernel::System::State')->StateGetStatesByType(
+            StateType => [ 'pending reminder', 'pending auto' ],
+            Result    => 'ID',
+        );
+    }
 
     # add JS data
     my %JSConfig = (
diff --git a/Kernel/System/Package.pm b/Kernel/System/Package.pm
index c60a3adeac..799ea96e0f 100644
--- a/Kernel/System/Package.pm
+++ b/Kernel/System/Package.pm
@@ -2571,7 +2571,11 @@ sub PackageInstallDefaultFiles {
     # get main object
     my $MainObject = $Kernel::OM->Get('Kernel::System::Main');
 
-    my $Directory    = $Self->{ConfigObject}->Get('Home') . '/var/packages';
+    my $Directory = $Self->{ConfigObject}->Get('Home') . '/var/packages';
+
+    # Return if the directory does not exist.
+    return if !-e $Directory;
+
     my @PackageFiles = $MainObject->DirectoryRead(
         Directory => $Directory,
         Filter    => '*.opm',