diff --git a/internal/api/backresthandler.go b/internal/api/backresthandler.go
index b3d50623..aeeb120d 100644
--- a/internal/api/backresthandler.go
+++ b/internal/api/backresthandler.go
@@ -20,6 +20,7 @@ import (
 	"github.com/garethgeorge/backrest/gen/go/v1/v1connect"
 	syncapi "github.com/garethgeorge/backrest/internal/api/syncapi"
 	"github.com/garethgeorge/backrest/internal/config"
+	"github.com/garethgeorge/backrest/internal/cryptoutil"
 	"github.com/garethgeorge/backrest/internal/env"
 	"github.com/garethgeorge/backrest/internal/logstore"
 	"github.com/garethgeorge/backrest/internal/oplog"
@@ -108,6 +109,10 @@ func (s *BackrestHandler) CheckRepoExists(ctx context.Context, req *connect.Requ
 		c.Repos = append(c.Repos, req.Msg)
 	}
 
+	if req.Msg.Guid == "" {
+		req.Msg.Guid = cryptoutil.MustRandomID(cryptoutil.DefaultIDBits)
+	}
+
 	if err := config.ValidateConfig(c); err != nil {
 		return nil, fmt.Errorf("validation error: %w", err)
 	}
@@ -126,7 +131,9 @@ func (s *BackrestHandler) CheckRepoExists(ctx context.Context, req *connect.Requ
 	defer cancel()
 
 	if err := r.Exists(ctx); err != nil {
-		if strings.Contains(err.Error(), "repository does not exist") {
+		zap.S().Debugf("repo %q exists or not: %v", req.Msg.Id, err)
+		if errors.Is(err, restic.ErrRepoNotFound) {
+			zap.S().Debugf("repo %q does not exist", req.Msg.Id)
 			return connect.NewResponse(&types.BoolValue{Value: false}), nil
 		}
 		return nil, err
diff --git a/pkg/restic/restic.go b/pkg/restic/restic.go
index 17f40746..a469602d 100644
--- a/pkg/restic/restic.go
+++ b/pkg/restic/restic.go
@@ -22,6 +22,7 @@ var errAlreadyInitialized = errors.New("repo already initialized")
 var ErrPartialBackup = errors.New("incomplete backup")
 var ErrBackupFailed = errors.New("backup failed")
 var ErrRestoreFailed = errors.New("restore failed")
+var ErrRepoNotFound = errors.New("repo does not exist")
 
 type Repo struct {
 	cmd string
@@ -99,6 +100,10 @@ func (r *Repo) Exists(ctx context.Context, opts ...GenericOption) error {
 		cmd := r.commandWithContext(ctx, []string{"cat", "config"}, opts...)
 		r.pipeCmdOutputToWriter(cmd, output)
 		if err := cmd.Run(); err != nil {
+			var exitErr *exec.ExitError
+			if errors.As(err, &exitErr) && exitErr.ExitCode() == 10 {
+				err = ErrRepoNotFound
+			}
 			r.exists = newCmdError(ctx, cmd, newErrorWithOutput(err, output.String()))
 		} else if err := json.Unmarshal(output.Bytes(), &r.repoConfig); err != nil {
 			r.exists = newCmdError(ctx, cmd, newErrorWithOutput(fmt.Errorf("command output is not valid JSON: %w", err), output.String()))
diff --git a/webui/src/views/AddRepoModal.tsx b/webui/src/views/AddRepoModal.tsx
index 1bce89de..7bc9e793 100644
--- a/webui/src/views/AddRepoModal.tsx
+++ b/webui/src/views/AddRepoModal.tsx
@@ -209,7 +209,7 @@ export const AddRepoModal = ({ template }: { template: Repo | null }) => {
               });
               try {
                 const exists = await backrestService.checkRepoExists(repo);
-                if (exists) {
+                if (exists.value) {
                   alertsApi.success(
                     "Connected successfully to " +
                       repo.uri +