diff --git a/cmd/restic/cmd_backup_test.go b/cmd/restic/cmd_backup_test.go
index 90e9a5a4b..49642b872 100644
--- a/cmd/restic/cmd_backup_test.go
+++ b/cmd/restic/cmd_backup_test.go
@@ -32,7 +32,7 @@ func TestCollectTargets(t *testing.T) {
 		// All mentioned files must exist for collectTargets.
 		f, err := os.Create(filepath.Join(dir, filename))
 		rtest.OK(t, err)
-		f.Close()
+		rtest.OK(t, f.Close())
 
 		expect = append(expect, f.Name())
 	}
@@ -41,7 +41,7 @@ func TestCollectTargets(t *testing.T) {
 	rtest.OK(t, err)
 	// Empty lines should be ignored. A line starting with '#' is a comment.
 	fmt.Fprintf(f1, "\n%s*\n # here's a comment\n", f1.Name())
-	f1.Close()
+	rtest.OK(t, f1.Close())
 
 	f2, err := os.Create(filepath.Join(dir, "fromfile-verbatim"))
 	rtest.OK(t, err)
@@ -49,7 +49,7 @@ func TestCollectTargets(t *testing.T) {
 		// Empty lines should be ignored. CR+LF is allowed.
 		fmt.Fprintf(f2, "%s\r\n\n", filepath.Join(dir, filename))
 	}
-	f2.Close()
+	rtest.OK(t, f2.Close())
 
 	f3, err := os.Create(filepath.Join(dir, "fromfile-raw"))
 	rtest.OK(t, err)
@@ -57,7 +57,7 @@ func TestCollectTargets(t *testing.T) {
 		fmt.Fprintf(f3, "%s\x00", filepath.Join(dir, filename))
 	}
 	rtest.OK(t, err)
-	f3.Close()
+	rtest.OK(t, f3.Close())
 
 	opts := BackupOptions{
 		FilesFrom:         []string{f1.Name()},
diff --git a/cmd/restic/cmd_cache.go b/cmd/restic/cmd_cache.go
index 89fb2c0df..1b36219eb 100644
--- a/cmd/restic/cmd_cache.go
+++ b/cmd/restic/cmd_cache.go
@@ -148,7 +148,7 @@ func runCache(opts CacheOptions, gopts GlobalOptions, args []string) error {
 		})
 	}
 
-	tab.Write(gopts.stdout)
+	_ = tab.Write(gopts.stdout)
 	Printf("%d cache dirs in %s\n", len(dirs), cachedir)
 
 	return nil
diff --git a/cmd/restic/cmd_find.go b/cmd/restic/cmd_find.go
index 0986b5a13..378d6cbdc 100644
--- a/cmd/restic/cmd_find.go
+++ b/cmd/restic/cmd_find.go
@@ -563,7 +563,10 @@ func runFind(opts FindOptions, gopts GlobalOptions, args []string) error {
 	}
 
 	if opts.PackID {
-		f.packsToBlobs(ctx, []string{f.pat.pattern[0]}) // TODO: support multiple packs
+		err := f.packsToBlobs(ctx, []string{f.pat.pattern[0]}) // TODO: support multiple packs
+		if err != nil {
+			return err
+		}
 	}
 
 	for sn := range FindFilteredSnapshots(ctx, repo, opts.Hosts, opts.Tags, opts.Paths, opts.Snapshots) {
diff --git a/cmd/restic/cmd_ls.go b/cmd/restic/cmd_ls.go
index db908a72c..90106e8a5 100644
--- a/cmd/restic/cmd_ls.go
+++ b/cmd/restic/cmd_ls.go
@@ -159,16 +159,17 @@ func runLs(opts LsOptions, gopts GlobalOptions, args []string) error {
 		enc := json.NewEncoder(gopts.stdout)
 
 		printSnapshot = func(sn *restic.Snapshot) {
-			enc.Encode(lsSnapshot{
+			err = enc.Encode(lsSnapshot{
 				Snapshot:   sn,
 				ID:         sn.ID(),
 				ShortID:    sn.ID().Str(),
 				StructType: "snapshot",
 			})
+			panic(err)
 		}
 
 		printNode = func(path string, node *restic.Node) {
-			enc.Encode(lsNode{
+			err = enc.Encode(lsNode{
 				Name:       node.Name,
 				Type:       node.Type,
 				Path:       path,
@@ -181,6 +182,7 @@ func runLs(opts LsOptions, gopts GlobalOptions, args []string) error {
 				ChangeTime: node.ChangeTime,
 				StructType: "node",
 			})
+			panic(err)
 		}
 	} else {
 		printSnapshot = func(sn *restic.Snapshot) {
diff --git a/cmd/restic/cmd_recover.go b/cmd/restic/cmd_recover.go
index 8f11b6860..c6b111d22 100644
--- a/cmd/restic/cmd_recover.go
+++ b/cmd/restic/cmd_recover.go
@@ -117,7 +117,10 @@ func runRecover(gopts GlobalOptions) error {
 			ModTime:    time.Now(),
 			ChangeTime: time.Now(),
 		}
-		tree.Insert(&node)
+		err = tree.Insert(&node)
+		if err != nil {
+			return err
+		}
 	}
 
 	treeID, err := repo.SaveTree(gopts.ctx, tree)
diff --git a/cmd/restic/cmd_snapshots.go b/cmd/restic/cmd_snapshots.go
index 300ba99ee..091861bfa 100644
--- a/cmd/restic/cmd_snapshots.go
+++ b/cmd/restic/cmd_snapshots.go
@@ -243,7 +243,10 @@ func PrintSnapshots(stdout io.Writer, list restic.Snapshots, reasons []restic.Ke
 		}
 	}
 
-	tab.Write(stdout)
+	err := tab.Write(stdout)
+	if err != nil {
+		Warnf("error printing: %v\n", err)
+	}
 }
 
 // PrintSnapshotGroupHeader prints which group of the group-by option the
diff --git a/cmd/restic/cmd_snapshots_test.go b/cmd/restic/cmd_snapshots_test.go
index 04af1a3c1..777c4272f 100644
--- a/cmd/restic/cmd_snapshots_test.go
+++ b/cmd/restic/cmd_snapshots_test.go
@@ -11,7 +11,8 @@ import (
 func TestEmptySnapshotGroupJSON(t *testing.T) {
 	for _, grouped := range []bool{false, true} {
 		var w strings.Builder
-		printSnapshotGroupJSON(&w, nil, grouped)
+		err := printSnapshotGroupJSON(&w, nil, grouped)
+		rtest.OK(t, err)
 
 		rtest.Equals(t, "[]", strings.TrimSpace(w.String()))
 	}
diff --git a/cmd/restic/delete.go b/cmd/restic/delete.go
index e9b2481e0..26ca08196 100644
--- a/cmd/restic/delete.go
+++ b/cmd/restic/delete.go
@@ -9,7 +9,7 @@ import (
 // DeleteFiles deletes the given fileList of fileType in parallel
 // it will print a warning if there is an error, but continue deleting the remaining files
 func DeleteFiles(gopts GlobalOptions, repo restic.Repository, fileList restic.IDSet, fileType restic.FileType) {
-	deleteFiles(gopts, true, repo, fileList, fileType)
+	_ = deleteFiles(gopts, true, repo, fileList, fileType)
 }
 
 // DeleteFilesChecked deletes the given fileList of fileType in parallel
diff --git a/cmd/restic/exclude.go b/cmd/restic/exclude.go
index e63c689ec..1ddd8932c 100644
--- a/cmd/restic/exclude.go
+++ b/cmd/restic/exclude.go
@@ -180,7 +180,9 @@ func isDirExcludedByFile(dir, tagFilename, header string) bool {
 		Warnf("could not open exclusion tagfile: %v", err)
 		return false
 	}
-	defer f.Close()
+	defer func() {
+		_ = f.Close()
+	}()
 	buf := make([]byte, len(header))
 	_, err = io.ReadFull(f, buf)
 	// EOF is handled with a dedicated message, otherwise the warning were too cryptic
diff --git a/cmd/restic/integration_test.go b/cmd/restic/integration_test.go
index d17602d0b..1e39301f3 100644
--- a/cmd/restic/integration_test.go
+++ b/cmd/restic/integration_test.go
@@ -566,9 +566,9 @@ func TestBackupErrors(t *testing.T) {
 
 	// Assume failure
 	inaccessibleFile := filepath.Join(env.testdata, "0", "0", "9", "0")
-	os.Chmod(inaccessibleFile, 0000)
+	rtest.OK(t, os.Chmod(inaccessibleFile, 0000))
 	defer func() {
-		os.Chmod(inaccessibleFile, 0644)
+		rtest.OK(t, os.Chmod(inaccessibleFile, 0644))
 	}()
 	opts := BackupOptions{}
 	gopts := env.gopts
@@ -933,7 +933,7 @@ func testRunKeyAddNewKeyUserHost(t testing.TB, gopts GlobalOptions) {
 		keyHostname = ""
 	}()
 
-	cmdKey.Flags().Parse([]string{"--user=john", "--host=example.com"})
+	rtest.OK(t, cmdKey.Flags().Parse([]string{"--user=john", "--host=example.com"}))
 
 	t.Log("adding key for john@example.com")
 	rtest.OK(t, runKey(gopts, []string{"add"}))
@@ -1106,7 +1106,7 @@ func TestRestoreLatest(t *testing.T) {
 	testRunBackup(t, "", []string{filepath.Base(env.testdata)}, opts, env.gopts)
 	testRunCheck(t, env.gopts)
 
-	os.Remove(p)
+	rtest.OK(t, os.Remove(p))
 	rtest.OK(t, appendRandomData(p, 101))
 	testRunBackup(t, "", []string{filepath.Base(env.testdata)}, opts, env.gopts)
 	testRunCheck(t, env.gopts)
@@ -1747,16 +1747,32 @@ func copyFile(dst string, src string) error {
 	if err != nil {
 		return err
 	}
-	defer srcFile.Close()
 
 	dstFile, err := os.Create(dst)
 	if err != nil {
+		// ignore subsequent errors
+		_ = srcFile.Close()
 		return err
 	}
-	defer dstFile.Close()
 
 	_, err = io.Copy(dstFile, srcFile)
-	return err
+	if err != nil {
+		// ignore subsequent errors
+		_ = srcFile.Close()
+		_ = dstFile.Close()
+	}
+
+	err = srcFile.Close()
+	if err != nil {
+		return err
+	}
+
+	err = dstFile.Close()
+	if err != nil {
+		return err
+	}
+
+	return nil
 }
 
 var diffOutputRegexPatterns = []string{
diff --git a/internal/archiver/archiver.go b/internal/archiver/archiver.go
index 2b0ac4ada..235898df0 100644
--- a/internal/archiver/archiver.go
+++ b/internal/archiver/archiver.go
@@ -405,7 +405,10 @@ func (arch *Archiver) Save(ctx context.Context, snPath, target string, previous
 			debug.Log("%v hasn't changed, but contents are missing!", target)
 			// There are contents missing - inform user!
 			err := errors.Errorf("parts of %v not found in the repository index; storing the file again", target)
-			arch.error(abstarget, fi, err)
+			err = arch.error(abstarget, fi, err)
+			if err != nil {
+				return FutureNode{}, false, err
+			}
 		}
 
 		// reopen file and do an fstat() on the open file to check it is still
@@ -457,7 +460,10 @@ func (arch *Archiver) Save(ctx context.Context, snPath, target string, previous
 		start := time.Now()
 		oldSubtree, err := arch.loadSubtree(ctx, previous)
 		if err != nil {
-			arch.error(abstarget, fi, err)
+			err = arch.error(abstarget, fi, err)
+		}
+		if err != nil {
+			return FutureNode{}, false, err
 		}
 
 		fn.isTree = true
@@ -592,7 +598,10 @@ func (arch *Archiver) SaveTree(ctx context.Context, snPath string, atree *Tree,
 		oldNode := previous.Find(name)
 		oldSubtree, err := arch.loadSubtree(ctx, oldNode)
 		if err != nil {
-			arch.error(join(snPath, name), nil, err)
+			err = arch.error(join(snPath, name), nil, err)
+		}
+		if err != nil {
+			return nil, err
 		}
 
 		// not a leaf node, archive subtree
@@ -751,7 +760,7 @@ func (arch *Archiver) loadParentTree(ctx context.Context, snapshotID restic.ID)
 	tree, err := arch.Repo.LoadTree(ctx, *sn.Tree)
 	if err != nil {
 		debug.Log("unable to load tree %v: %v", *sn.Tree, err)
-		arch.error("/", nil, arch.wrapLoadTreeError(*sn.Tree, err))
+		_ = arch.error("/", nil, arch.wrapLoadTreeError(*sn.Tree, err))
 		return nil
 	}
 	return tree