diff --git a/bot/handle_link.go b/bot/handle_link.go
index bd105ac..6465745 100644
--- a/bot/handle_link.go
+++ b/bot/handle_link.go
@@ -1,6 +1,7 @@
 package bot
 
 import (
+	"fmt"
 	"regexp"
 	"strconv"
 	"strings"
@@ -41,6 +42,11 @@ func handleLinkMessage(ctx *ext.Context, update *ext.Update) error {
 		ctx.Reply(update, ext.ReplyTextString("Failed to resolve chat ID"), nil)
 		return dispatcher.EndGroups
 	}
+	if linkChat == nil {
+		logger.L.Errorf("Cannot find chat: %s", chatUsername)
+		ctx.Reply(update, ext.ReplyTextString("Cannot find chat"), nil)
+		return dispatcher.EndGroups
+	}
 	user, err := dao.GetUserByUserID(update.GetUserChat().GetID())
 	if err != nil {
 		logger.L.Errorf("Failed to get user: %s", err)
@@ -59,12 +65,10 @@ func handleLinkMessage(ctx *ext.Context, update *ext.Update) error {
 		return dispatcher.EndGroups
 	}
 	if file.FileName == "" {
-		ctx.EditMessage(update.EffectiveChat().GetID(), &tg.MessagesEditMessageRequest{
-			Message: "无法获取文件名",
-			ID:      replied.ID,
-		})
-		return dispatcher.EndGroups
+		logger.L.Warnf("Empty file name, use generated name")
+		file.FileName = fmt.Sprintf("%d_%d_%s", linkChat.GetID(), messageID, file.Hash())
 	}
+
 	receivedFile := &types.ReceivedFile{
 		Processing:     false,
 		FileName:       file.FileName,
diff --git a/bot/handlers.go b/bot/handlers.go
index e8bf785..52258da 100644
--- a/bot/handlers.go
+++ b/bot/handlers.go
@@ -1,7 +1,6 @@
 package bot
 
 import (
-	"errors"
 	"fmt"
 	"strconv"
 	"strings"
@@ -183,20 +182,14 @@ func saveCmd(ctx *ext.Context, update *ext.Update) error {
 	if err != nil {
 		logger.L.Errorf("Failed to get file from message: %s", err)
 		ctx.EditMessage(update.EffectiveChat().GetID(), &tg.MessagesEditMessageRequest{
-			Message: "获取文件失败: " + err.Error(),
+			Message: fmt.Sprintf("获取文件失败: %s", err),
 			ID:      replied.ID,
 		})
 		return dispatcher.EndGroups
 	}
-
 	if file.FileName == "" {
-		ctx.EditMessage(update.EffectiveChat().GetID(), &tg.MessagesEditMessageRequest{
-			Message: "无法获取文件名, 请使用 /save <自定义文件名> 回复此文件",
-			ID:      replied.ID,
-		})
-		return dispatcher.EndGroups
+		file.FileName = fmt.Sprintf("%d_%d_%s", update.EffectiveChat().GetID(), replyToMsgID, file.Hash())
 	}
-
 	receivedFile := &types.ReceivedFile{
 		Processing:     false,
 		FileName:       file.FileName,
@@ -301,16 +294,11 @@ func handleFileMessage(ctx *ext.Context, update *ext.Update) error {
 	file, err := FileFromMedia(media, "")
 	if err != nil {
 		logger.L.Errorf("Failed to get file from media: %s", err)
-		if errors.Is(err, ErrEmptyFileName) {
-			ctx.Reply(update, ext.ReplyTextString("无法获取文件名, 请使用 /save <自定义文件名> 回复此文件"), nil)
-		} else {
-			ctx.Reply(update, ext.ReplyTextString(fmt.Sprintf("获取文件失败: %s", err)), nil)
-		}
+		ctx.Reply(update, ext.ReplyTextString(fmt.Sprintf("获取文件失败: %s", err)), nil)
 		return dispatcher.EndGroups
 	}
 	if file.FileName == "" {
-		ctx.Reply(update, ext.ReplyTextString("无法获取文件名"), nil)
-		return dispatcher.EndGroups
+		file.FileName = fmt.Sprintf("%d_%d_%s", update.EffectiveChat().GetID(), update.EffectiveMessage.ID, file.Hash())
 	}
 
 	if err := dao.SaveReceivedFile(&types.ReceivedFile{
diff --git a/bot/utils.go b/bot/utils.go
index e996b48..39091a7 100644
--- a/bot/utils.go
+++ b/bot/utils.go
@@ -18,7 +18,6 @@ import (
 )
 
 var (
-	ErrEmptyFileName   = errors.New("file name is empty")
 	ErrEmptyDocument   = errors.New("document is empty")
 	ErrEmptyPhoto      = errors.New("photo is empty")
 	ErrEmptyPhotoSize  = errors.New("photo size is empty")
@@ -105,9 +104,6 @@ func FileFromMedia(media tg.MessageMediaClass, customFileName string) (*types.Fi
 				break
 			}
 		}
-		if fileName == "" {
-			return nil, ErrEmptyFileName
-		}
 		return &types.File{
 			Location: document.AsInputDocumentFileLocation(),
 			FileSize: document.Size,
diff --git a/core/core.go b/core/core.go
index 8a1f23e..597f92c 100644
--- a/core/core.go
+++ b/core/core.go
@@ -10,6 +10,8 @@ import (
 	"path/filepath"
 	"time"
 
+	"github.com/gabriel-vasile/mimetype"
+
 	"github.com/celestix/gotgproto/ext"
 	"github.com/duke-git/lancet/v2/fileutil"
 	"github.com/gotd/td/tg"
@@ -22,6 +24,9 @@ import (
 
 func processPendingTask(task *types.Task) error {
 	logger.L.Debugf("Start processing task: %s", task.String())
+	if task.FileName() == "" {
+		task.File.FileName = fmt.Sprintf("%d_%d_%s", task.FileChatID, task.FileMessageID, task.File.Hash())
+	}
 	cacheDestPath := filepath.Join(config.Cfg.Temp.BasePath, task.FileName())
 	cacheDestPath, err := filepath.Abs(cacheDestPath)
 	if err != nil {
@@ -71,6 +76,7 @@ func processPendingTask(task *types.Task) error {
 		Entities: entities,
 		ID:       task.ReplyMessageID,
 	})
+
 	readCloser, err := NewTelegramReader(task.Ctx, bot.Client, &task.File.Location,
 		0, task.File.FileSize-1, task.File.FileSize,
 		progressCallback, task.File.FileSize/100)
@@ -88,8 +94,16 @@ func processPendingTask(task *types.Task) error {
 	if _, err := io.CopyN(dest, readCloser, task.File.FileSize); err != nil {
 		return fmt.Errorf("failed to download file: %w", err)
 	}
-
 	defer cleanCacheFile(cacheDestPath)
+	if path.Ext(task.FileName()) == "" {
+		mimeType, err := mimetype.DetectFile(cacheDestPath)
+		if err != nil {
+			logger.L.Errorf("Failed to detect mime type: %s", err)
+		} else {
+			task.File.FileName = fmt.Sprintf("%s%s", task.FileName(), mimeType.Extension())
+			task.StoragePath = fmt.Sprintf("%s%s", task.StoragePath, mimeType.Extension())
+		}
+	}
 
 	logger.L.Infof("Downloaded file: %s", cacheDestPath)
 	ctx.EditMessage(task.ReplyChatID, &tg.MessagesEditMessageRequest{
diff --git a/go.mod b/go.mod
index 49b240d..390d7f0 100644
--- a/go.mod
+++ b/go.mod
@@ -24,6 +24,7 @@ require (
 	github.com/dlclark/regexp2 v1.11.5 // indirect
 	github.com/dustin/go-humanize v1.0.1 // indirect
 	github.com/fatih/color v1.18.0 // indirect
+	github.com/gabriel-vasile/mimetype v1.4.8 // indirect
 	github.com/ghodss/yaml v1.0.0 // indirect
 	github.com/glebarez/go-sqlite v1.22.0 // indirect
 	github.com/go-faster/errors v0.7.1 // indirect
diff --git a/go.sum b/go.sum
index 4eb9bc7..7a36da0 100644
--- a/go.sum
+++ b/go.sum
@@ -34,6 +34,8 @@ github.com/frankban/quicktest v1.14.6/go.mod h1:4ptaffx2x8+WTWXmUCuVU6aPUX1/Mz7z
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/fsnotify/fsnotify v1.8.0 h1:dAwr6QBTBZIkG8roQaJjGof0pp0EeF+tNV7YBP3F/8M=
 github.com/fsnotify/fsnotify v1.8.0/go.mod h1:8jBTzvmWwFyi3Pb8djgCCO5IBqzKJ/Jwo8TRcHyHii0=
+github.com/gabriel-vasile/mimetype v1.4.8 h1:FfZ3gj38NjllZIeJAmMhr+qKL8Wu+nOoI3GqacKw1NM=
+github.com/gabriel-vasile/mimetype v1.4.8/go.mod h1:ByKUIKGjh1ODkGM1asKUbQZOLGrPjydw3hYPU2YU9t8=
 github.com/ghodss/yaml v1.0.0 h1:wQHKEahhL6wmXdzwWG11gIVCkOv05bNOh+Rxn0yngAk=
 github.com/ghodss/yaml v1.0.0/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
 github.com/glebarez/go-sqlite v1.22.0 h1:uAcMJhaA6r3LHMTFgP0SifzgXg46yJkgxqyuyec+ruQ=
diff --git a/types/types.go b/types/types.go
index ec36bd5..e7c522e 100644
--- a/types/types.go
+++ b/types/types.go
@@ -2,6 +2,8 @@ package types
 
 import (
 	"context"
+	"crypto/md5"
+	"encoding/hex"
 	"fmt"
 	"time"
 
@@ -56,3 +58,18 @@ type File struct {
 	FileSize int64
 	FileName string
 }
+
+func (f File) Hash() string {
+	locationBytes := []byte(f.Location.String())
+	fileSizeBytes := []byte(fmt.Sprintf("%d", f.FileSize))
+	fileNameBytes := []byte(f.FileName)
+
+	structBytes := append(locationBytes, fileSizeBytes...)
+	structBytes = append(structBytes, fileNameBytes...)
+
+	hash := md5.New()
+	hash.Write(structBytes)
+	hashBytes := hash.Sum(nil)
+
+	return hex.EncodeToString(hashBytes)
+}