diff --git a/commands/command_clean.go b/commands/command_clean.go
index 2be74b2f..314beee8 100644
--- a/commands/command_clean.go
+++ b/commands/command_clean.go
@@ -22,7 +22,7 @@ import (
 //
 // If the object read from "from" is _already_ a clean pointer, then it will be
 // written out verbatim to "to", without trying to make it a pointer again.
-func clean(to io.Writer, from io.Reader, fileName string, fileSize int64) error {
+func clean(to io.Writer, from io.Reader, fileName string, fileSize int64) (*lfs.Pointer, error) {
 	var cb progress.CopyCallback
 	var file *os.File
 
@@ -58,7 +58,7 @@ func clean(to io.Writer, from io.Reader, fileName string, fileSize int64) error
 		// containing the bytes that we should write back out to Git.
 
 		_, err = to.Write(errors.GetContext(err, "bytes").([]byte))
-		return err
+		return nil, err
 	}
 
 	if err != nil {
@@ -85,7 +85,7 @@ func clean(to io.Writer, from io.Reader, fileName string, fileSize int64) error
 	}
 
 	_, err = lfs.EncodePointer(to, cleaned.Pointer)
-	return err
+	return cleaned.Pointer, err
 }
 
 func cleanCommand(cmd *cobra.Command, args []string) {
@@ -97,9 +97,14 @@ func cleanCommand(cmd *cobra.Command, args []string) {
 		fileName = args[0]
 	}
 
-	if err := clean(os.Stdout, os.Stdin, fileName, -1); err != nil {
+	ptr, err := clean(os.Stdout, os.Stdin, fileName, -1)
+	if err != nil {
 		Error(err.Error())
 	}
+
+	if ptr != nil && possiblyMalformedObjectSize(ptr.Size) {
+		Error("Possibly malformed conversion on Windows, see `git lfs help smudge` for more details.")
+	}
 }
 
 func init() {
diff --git a/commands/command_filter_process.go b/commands/command_filter_process.go
index 3edc5914..a2018c61 100644
--- a/commands/command_filter_process.go
+++ b/commands/command_filter_process.go
@@ -63,7 +63,13 @@ func filterCommand(cmd *cobra.Command, args []string) {
 		switch req.Header["command"] {
 		case "clean":
 			w = git.NewPktlineWriter(os.Stdout, cleanFilterBufferCapacity)
-			err = clean(w, req.Payload, req.Header["pathname"], -1)
+
+			var ptr *lfs.Pointer
+			ptr, err = clean(w, req.Payload, req.Header["pathname"], -1)
+
+			if ptr != nil {
+				n = ptr.Size
+			}
 		case "smudge":
 			w = git.NewPktlineWriter(os.Stdout, smudgeFilterBufferCapacity)
 			n, err = smudge(w, req.Payload, req.Header["pathname"], skip, filter)
@@ -74,7 +80,7 @@ func filterCommand(cmd *cobra.Command, args []string) {
 		if errors.IsNotAPointerError(err) {
 			malformed = append(malformed, req.Header["pathname"])
 			err = nil
-		} else if possiblyMalformedSmudge(n) {
+		} else if possiblyMalformedObjectSize(n) {
 			malformedOnWindows = append(malformedOnWindows, req.Header["pathname"])
 		}
 
diff --git a/commands/command_migrate_import.go b/commands/command_migrate_import.go
index 501f9eeb..6920c0ef 100644
--- a/commands/command_migrate_import.go
+++ b/commands/command_migrate_import.go
@@ -35,7 +35,7 @@ func migrateImportCommand(cmd *cobra.Command, args []string) {
 
 			var buf bytes.Buffer
 
-			if err := clean(&buf, b.Contents, path, b.Size); err != nil {
+			if _, err := clean(&buf, b.Contents, path, b.Size); err != nil {
 				return nil, err
 			}
 
diff --git a/commands/command_smudge.go b/commands/command_smudge.go
index ffedc8b6..276e181f 100644
--- a/commands/command_smudge.go
+++ b/commands/command_smudge.go
@@ -101,7 +101,7 @@ func smudgeCommand(cmd *cobra.Command, args []string) {
 		} else {
 			Error(err.Error())
 		}
-	} else if possiblyMalformedSmudge(n) {
+	} else if possiblyMalformedObjectSize(n) {
 		fmt.Fprintln(os.Stderr, "Possibly malformed smudge on Windows: see `git lfs help smudge` for more info.")
 	}
 }
@@ -113,7 +113,7 @@ func smudgeFilename(args []string) string {
 	return "<unknown file>"
 }
 
-func possiblyMalformedSmudge(n int64) bool {
+func possiblyMalformedObjectSize(n int64) bool {
 	return n > 4*humanize.Gigabyte
 }