diff --git a/eeschema/dialogs/dialog_global_sym_lib_table_config.cpp b/eeschema/dialogs/dialog_global_sym_lib_table_config.cpp
index a62d776233..b0d1e6ea0c 100644
--- a/eeschema/dialogs/dialog_global_sym_lib_table_config.cpp
+++ b/eeschema/dialogs/dialog_global_sym_lib_table_config.cpp
@@ -57,11 +57,10 @@ bool DIALOG_GLOBAL_SYM_LIB_TABLE_CONFIG::TransferDataFromWindow()
         }
         catch( const IO_ERROR& ioe )
         {
-            DisplayError( this,
-                          wxString::Format( _( "Error occurred writing empty symbol library table "
-                                               "file.\n\n%s" ),
-                                            SYMBOL_LIB_TABLE::GetGlobalTableFileName(),
-                                            ioe.What() ) );
+            DisplayError( this, wxString::Format( _( "Error occurred writing empty symbol library "
+                                                     "table.\n\n%s" ),
+                                                  SYMBOL_LIB_TABLE::GetGlobalTableFileName(),
+                                                  ioe.What() ) );
             return false;
         }
 
@@ -81,8 +80,7 @@ bool DIALOG_GLOBAL_SYM_LIB_TABLE_CONFIG::TransferDataFromWindow()
     // Make sure the symbol library table to copy actually exists.
     if( !fn.FileExists() )
     {
-        DisplayError( this,
-                      wxString::Format( _( "File \"%s\" not found." ), fn.GetFullPath() ) );
+        DisplayError( this, wxString::Format( _( "File '%s' not found." ), fn.GetFullPath() ) );
         return false;
     }
 
@@ -95,9 +93,9 @@ bool DIALOG_GLOBAL_SYM_LIB_TABLE_CONFIG::TransferDataFromWindow()
     }
     catch( const IO_ERROR& ioe )
     {
-        DisplayError( this,
-                      wxString::Format( _( "File \"%s\" is not a valid symbol library table "
-                                           "file.\n\n%s" ), fn.GetFullPath(), ioe.What() ) );
+        DisplayError( this, wxString::Format( _( "'%s' is not a valid symbol library table.\n\n%s" ),
+                                              fn.GetFullPath(),
+                                              ioe.What() ) );
         return false;
     }
 
@@ -106,19 +104,18 @@ bool DIALOG_GLOBAL_SYM_LIB_TABLE_CONFIG::TransferDataFromWindow()
 
     if( !symTableFileName.DirExists() && !symTableFileName.Mkdir( 0x777, wxPATH_MKDIR_FULL ) )
     {
-        DisplayError( this,
-                      wxString::Format( _( "Cannot create global library table path \"%s\"." ),
-                                            symTableFileName.GetPath() ) );
+        DisplayError( this, wxString::Format( _( "Cannot create global library table path '%s'." ),
+                                              symTableFileName.GetPath() ) );
         return false;
     }
 
     // Copy the global symbol library table file to the user config.
     if( !::wxCopyFile( fn.GetFullPath(), symTableFileName.GetFullPath() ) )
     {
-        DisplayError( this,
-                      wxString::Format( _( "Cannot copy global symbol library table "
-                                           "file:\n\n \"%s\"\n\n:to:\n\n\"%s\"." ),
-                                        fn.GetFullPath(), symTableFileName.GetFullPath() ) );
+        DisplayError( this, wxString::Format( _( "Cannot copy global symbol library table file "
+                                                 "'%s' to '%s'." ),
+                                              fn.GetFullPath(),
+                                              symTableFileName.GetFullPath() ) );
         return false;
     }
 
@@ -132,9 +129,9 @@ bool DIALOG_GLOBAL_SYM_LIB_TABLE_CONFIG::TransferDataFromWindow()
     }
     catch( const IO_ERROR& ioe )
     {
-        DisplayError( this,
-                      wxString::Format( _( "Error occurred loading global symbol library table:"
-                                           "\n\n%s" ), ioe.What() ) );
+        DisplayError( this, wxString::Format( _( "Error occurred loading global symbol library "
+                                                 "table.\n\n%s" ),
+                                              ioe.What() ) );
         return false;
     }
 
diff --git a/eeschema/erc.cpp b/eeschema/erc.cpp
index 0831820155..22d2f14b98 100644
--- a/eeschema/erc.cpp
+++ b/eeschema/erc.cpp
@@ -675,8 +675,9 @@ int ERC_TESTER::TestLibSymbolIssues()
 {
     wxCHECK( m_schematic, 0 );
 
-    wxString    msg;
-    int         err_count = 0;
+    SYMBOL_LIB_TABLE* libTable = m_schematic->Prj().SchSymbolLibTable();
+    wxString          msg;
+    int               err_count = 0;
 
     SCH_SCREENS screens( m_schematic->Root() );
 
@@ -690,38 +691,65 @@ int ERC_TESTER::TestLibSymbolIssues()
 
             wxCHECK2( symbol, continue );
 
-            LIB_PART* libSymbolInSchematic = screen->GetLibSymbols()[
-                    symbol->GetLibId().GetUniStringLibId() ];
+            wxString  libIdStr = symbol->GetLibId().GetUniStringLibId();
+            LIB_PART* libSymbolInSchematic = screen->GetLibSymbols()[ libIdStr ];
 
             wxCHECK2( libSymbolInSchematic, continue );
 
-            LIB_PART* libSymbol = SchGetLibPart( symbol->GetLibId(),
-                                                 m_schematic->Prj().SchSymbolLibTable() );
+            wxString       libName = symbol->GetLibId().GetLibNickname();
+            LIB_TABLE_ROW* libTableRow = libTable->FindRow( libName );
+
+            if( !libTableRow )
+            {
+                std::shared_ptr<ERC_ITEM> ercItem = ERC_ITEM::Create( ERCE_LIB_SYMBOL_ISSUES );
+                ercItem->SetItems( symbol );
+                msg.Printf( _( "The current configuration does not include the library '%s'." ),
+                            libName );
+                ercItem->SetErrorMessage( msg );
+
+                markers.emplace_back( new SCH_MARKER( ercItem, symbol->GetPosition() ) );
+                break;
+            }
+            else if( !libTable->HasLibrary( libName, true ) )
+            {
+                std::shared_ptr<ERC_ITEM> ercItem = ERC_ITEM::Create( ERCE_LIB_SYMBOL_ISSUES );
+                ercItem->SetItems( symbol );
+                msg.Printf( _( "The library '%s' is not enabled in the current configuration." ),
+                            libName );
+                ercItem->SetErrorMessage( msg );
+
+                markers.emplace_back( new SCH_MARKER( ercItem, symbol->GetPosition() ) );
+                break;
+            }
+
+            wxString  symbolName = symbol->GetLibId().GetLibItemName();
+            LIB_PART* libSymbol = SchGetLibPart( symbol->GetLibId(), libTable );
 
             if( libSymbol == nullptr )
             {
                 std::shared_ptr<ERC_ITEM> ercItem = ERC_ITEM::Create( ERCE_LIB_SYMBOL_ISSUES );
                 ercItem->SetItems( symbol );
-                msg.Printf( "Library symbol link \"%s\" cannot be found in symbol library table",
-                            symbol->GetLibId().GetUniStringLibId() );
+                msg.Printf( "Symbol '%s' not found in symbol library '%s'",
+                            symbolName,
+                            libName );
                 ercItem->SetErrorMessage( msg );
 
                 markers.emplace_back( new SCH_MARKER( ercItem, symbol->GetPosition() ) );
+                break;
             }
-            else
+
+            std::unique_ptr<LIB_PART> flattenedSymbol = libSymbol->Flatten();
+
+            if( *flattenedSymbol != *libSymbolInSchematic )
             {
-                std::unique_ptr<LIB_PART> flattenedSymbol = libSymbol->Flatten();
+                std::shared_ptr<ERC_ITEM> ercItem = ERC_ITEM::Create( ERCE_LIB_SYMBOL_ISSUES );
+                ercItem->SetItems( symbol );
+                msg.Printf( "Symbol '%s' has been modified in library '%s'.",
+                            symbolName,
+                            libName );
+                ercItem->SetErrorMessage( msg );
 
-                if( *flattenedSymbol != *libSymbolInSchematic )
-                {
-                    std::shared_ptr<ERC_ITEM> ercItem = ERC_ITEM::Create( ERCE_LIB_SYMBOL_ISSUES );
-                    ercItem->SetItems( symbol );
-                    msg.Printf( "Library symbol \"%s\" has been modified",
-                                symbol->GetLibId().GetUniStringLibId() );
-                    ercItem->SetErrorMessage( msg );
-
-                    markers.emplace_back( new SCH_MARKER( ercItem, symbol->GetPosition() ) );
-                }
+                markers.emplace_back( new SCH_MARKER( ercItem, symbol->GetPosition() ) );
             }
         }
 
diff --git a/eeschema/sch_base_frame.cpp b/eeschema/sch_base_frame.cpp
index 3448b34448..c4be430464 100644
--- a/eeschema/sch_base_frame.cpp
+++ b/eeschema/sch_base_frame.cpp
@@ -31,7 +31,6 @@
 #include <sch_view.h>
 #include <sch_painter.h>
 #include <settings/settings_manager.h>
-#include <gal/graphics_abstraction_layer.h>
 #include <confirm.h>
 #include <preview_items/selection_area.h>
 #include <class_library.h>
@@ -42,7 +41,6 @@
 #include <tool/tool_dispatcher.h>
 #include <tools/ee_actions.h>
 #include <tools/ee_selection_tool.h>
-#include <default_values.h>    // For some default values
 
 
 LIB_PART* SchGetLibPart( const LIB_ID& aLibId, SYMBOL_LIB_TABLE* aLibTable, PART_LIB* aCacheLib,