What causes "No base backup found." in MuntashirAkon/AppManager?

Pass options.relativeDir pointing at the specific backup directory instead of relying on the base backup.

MuntashirAkon/AppManager · error · BackupException

No base backup found.

Error message

No base backup found.

What it means

When RestoreOpOptions.relativeDir is null, restore() falls back to the 'base backup' recorded in the backup database for (userId, packageName). If BackupUtils.retrieveBaseBackupFromDb() returns null, there is no registered base backup, so the method throws BackupException('No base backup found.'). It means the backup metadata DB has no entry for that package/user.

Source

Thrown at app/src/main/java/io/github/muntashirakon/AppManager/backup/BackupManager.java:112

    public void restore(@NonNull RestoreOpOptions options, @Nullable ProgressHandler progressHandler)
            throws BackupException {
        if (options.packageName.equals("android")) {
            throw new BackupException("Android System (android) cannot be restored.");
        }
        if (options.flags.isEmpty()) {
            throw new BackupException("Restore is requested without any flags.");
        }
        BackupItems.BackupItem backupItem;
        try {
            if (options.relativeDir != null) {
                backupItem = BackupItems.findBackupItem(options.relativeDir);
            } else {
                // Use base backup
                Backup baseBackup = BackupUtils.retrieveBaseBackupFromDb(options.userId, options.packageName);
                if (baseBackup != null) {
                    backupItem = baseBackup.getItem();
                } else {
                    throw new BackupException("No base backup found.");
                }
            }
        } catch (IOException e) {
            throw new BackupException("Could not get backup files.", e);
        }
        if (progressHandler != null) {
            int max = calculateMaxProgress(options.flags);
            progressHandler.setProgressTextInterface(ProgressHandler.PROGRESS_PERCENT);
            progressHandler.postUpdate(max, 0f);
        }
        try (RestoreOp restoreOp = new RestoreOp(options.packageName, options.flags, backupItem, options.userId)) {
            restoreOp.runRestore(progressHandler);
            mRequiresRestart |= restoreOp.requiresRestart();
        }
    }

    public void deleteBackup(@NonNull DeleteOpOptions options) throws BackupException {
        List<BackupItems.BackupItem> backupItemList;

View on GitHub (pinned to 0152f468fc)

Solutions

Pass options.relativeDir pointing at the specific backup directory instead of relying on the base backup.
Re-import/register the existing backup folder so a base-backup entry is created in the DB.
Verify packageName and userId match the entry used when the backup was made.
Run a backup first (or use the UI's backup list) so a base backup exists, then restore.

Example fix

// before
options.relativeDir = null; // relies on base backup
// after
options.relativeDir = "com.example.app/20240101_120000"; // explicit backup dir

Defensive patterns

Strategy: validation

Validate before calling

Backup base = BackupUtils.retrieveBaseBackupFromDb(userId, pkg);
if (base == null) {
    throw new IllegalStateException("No base backup for " + pkg + " user " + userId + "; specify relativeDir");
}

Type guard

boolean hasBaseBackup(int userId, String pkg) {
    return BackupUtils.retrieveBaseBackupFromDb(userId, pkg) != null;
}

Try / catch

try {
    manager.restore(options, progress);
} catch (BackupException e) {
    if (e.getMessage().contains("No base backup")) { /* fall back to explicit relativeDir */ }
}

Prevention

Pass explicit relativeDir instead of relying on the base backup
Keep packageName/userId consistent with the backup-time values
Re-register backup folders after app reinstall so the DB is populated

When it happens

Trigger: Calling restore() without options.relativeDir for a package that has no base-backup row in the database (never backed up with this app, DB wiped, or backup files exist on disk but were never registered).

Common situations: Restoring on a fresh install of AppManager where the backup DB is empty but old backup folders still exist in the backup directory; wrong userId passed so the DB lookup targets the wrong user; typo in packageName.

Understand the failure class

Background: Record Not Found Errors: "not found", RecordNotFound, and "was not found" — what they mean and how to fix them — this error's family across 28 libraries.

Related errors

AI-assisted analysis of MuntashirAkon/AppManager@0152f468fc (2026-09-12). Data as JSON: /api/errors/d515755b91d828d7. Report an issue: GitHub.