diff --git a/src/db/localSwitchFilesDB.go b/src/db/localSwitchFilesDB.go
index d3b6719..b01f76f 100644
--- a/src/db/localSwitchFilesDB.go
+++ b/src/db/localSwitchFilesDB.go
@@ -6,6 +6,7 @@ import (
 	"os"
 	"path/filepath"
 	"regexp"
+	"runtime"
 	"strconv"
 	"strings"
 
@@ -17,7 +18,7 @@ import (
 
 var (
 	versionRegex = regexp.MustCompile(`\[[vV]?(?P<version>[0-9]{1,10})]`)
-	titleIdRegex = regexp.MustCompile(`\[(?P<titleId>[A-Z,a-z0-9]{16})]`)
+	titleIdRegex = regexp.MustCompile(`\[(?P<titleId>[A-Za-z0-9]{16})]`)
 )
 
 const (
@@ -134,6 +135,10 @@ func scanFolder(folder string, recursive bool, files *[]ExtendedFileInfo, progre
 			return nil
 		}
 
+		if runtime.GOOS == "darwin" && strings.EqualFold(info.Name(), ".ds_store") {
+			return nil
+		}
+
 		base := path[0 : len(path)-len(info.Name())]
 		if strings.TrimSuffix(base, string(os.PathSeparator)) != strings.TrimSuffix(folder, string(os.PathSeparator)) &&
 			!recursive {
@@ -167,6 +172,9 @@ func (ldb *LocalSwitchDBManager) processLocalFiles(files []ExtendedFileInfo,
 			ignoreFileTypes["."+strings.ToLower(ext)] = struct{}{}
 		}
 	}
+	if runtime.GOOS == "darwin" {
+		ignoreFileTypes[".ds_store"] = struct{}{}
+	}
 
 	ind := 0
 	total := len(files)
@@ -182,6 +190,10 @@ func (ldb *LocalSwitchDBManager) processLocalFiles(files []ExtendedFileInfo,
 			continue
 		}
 
+		if runtime.GOOS == "darwin" && strings.EqualFold(file.FileName, ".ds_store") {
+			continue
+		}
+
 		fileName := strings.ToLower(file.FileName)
 		isSplit := false
 
diff --git a/src/db/localSwitchFilesDB_test.go b/src/db/localSwitchFilesDB_test.go
new file mode 100644
index 0000000..464aa12
--- /dev/null
+++ b/src/db/localSwitchFilesDB_test.go
@@ -0,0 +1,25 @@
+package db
+
+import "testing"
+
+func TestParseTitleIdFromFileName(t *testing.T) {
+	fileName := "Super Mario [0100000000010000][v0].nsp"
+	titleId, err := parseTitleIdFromFileName(fileName)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if titleId == nil || *titleId != "0100000000010000" {
+		if titleId == nil {
+			t.Fatalf("expected title ID not nil")
+		}
+		t.Fatalf("expected 0100000000010000 got %v", *titleId)
+	}
+}
+
+func TestParseTitleIdFromFileNameInvalid(t *testing.T) {
+	fileName := "Invalid [01000000000100,0][v0].nsp"
+	_, err := parseTitleIdFromFileName(fileName)
+	if err == nil {
+		t.Fatalf("expected error for invalid title id")
+	}
+}
diff --git a/src/gui.go b/src/gui.go
index f7eb6ad..1816610 100644
--- a/src/gui.go
+++ b/src/gui.go
@@ -427,10 +427,10 @@ func (g *GUI) organizeLibrary() {
 		g.state.window.SendMessage(Message{Name: "error", Payload: "the organize options in settings.json are not valid, please check that the template contains file/folder name"}, func(m *astilectron.EventMessage) {})
 		return
 	}
-	process.OrganizeByFolders(folderToScan, g.state.localDB, g.state.switchDB, g)
 	if settings.ReadSettings(g.baseFolder).OrganizeOptions.DeleteOldUpdateFiles {
 		process.DeleteOldUpdates(g.baseFolder, g.state.localDB, g)
 	}
+	process.OrganizeByFolders(folderToScan, g.state.localDB, g.state.switchDB, g)
 }
 
 func (g *GUI) UpdateProgress(curr int, total int, message string) {
diff --git a/src/process/organizefolderStructure.go b/src/process/organizefolderStructure.go
index 6636075..c688772 100644
--- a/src/process/organizefolderStructure.go
+++ b/src/process/organizefolderStructure.go
@@ -25,7 +25,18 @@ func DeleteOldUpdates(baseFolder string, localDB *db.LocalSwitchFilesDB, updateP
 	i := 0
 	for k, v := range localDB.Skipped {
 		switch v.ReasonCode {
-		//case db.REASON_DUPLICATE:
+		case db.REASON_DUPLICATE:
+			fileToRemove := filepath.Join(k.BaseFolder, k.FileName)
+			if updateProgress != nil {
+				updateProgress.UpdateProgress(0, 0, "deleting "+fileToRemove)
+			}
+			zap.S().Infof("Deleting file: %v \n", fileToRemove)
+			err := os.Remove(fileToRemove)
+			if err != nil {
+				zap.S().Errorf("Failed to delete file  %v  [%v]\n", fileToRemove, err)
+				continue
+			}
+			i++
 		case db.REASON_OLD_UPDATE:
 			fileToRemove := filepath.Join(k.BaseFolder, k.FileName)
 			if updateProgress != nil {