BeyondDimension/SteamTools · warning · ApplicationException

no serial_number

Error message

no serial_number

What it means

Thrown during Steam Guard import when the deserialized SteamGuardModel has an empty/null SerialNumber. The serial is stored on the SteamAuthenticator and is needed for code generation/refresh, so its absence aborts import right after the shared-secret check.

Source

Thrown at src/BD.WTTS.Client.Plugins.Authenticator/UI/ViewModels/SteamGuardImportPageViewModel.cs:104

            if (string.IsNullOrEmpty(deviceId) || DeviceIdRegex().IsMatch(deviceId) == false)
                //WinAuthForm.ErrorDialog(this, "Invalid deviceid, expecting \"android:NNNN...\"");
                return;

            // check the steamguard
            byte[] secret;
            string? serial;
            var steamGuardModel = SJsonSerializer.Deserialize(PhoneImportSteamGuard,
                ImportFileModelJsonContext.Default.SteamGuardModel);

            if (steamGuardModel == null) return;

            if (string.IsNullOrEmpty(steamGuardModel.SharedSecret))
                throw new ApplicationException("no shared_secret");

            secret = Convert.FromBase64String(steamGuardModel.SharedSecret);

            if (string.IsNullOrEmpty(steamGuardModel.SerialNumber))
                throw new ApplicationException("no serial_number");

            serial = steamGuardModel.SerialNumber;

            var auth = new SteamAuthenticator
            {
                SecretKey = secret,
                Serial = serial,
                SteamData = PhoneImportSteamGuard,
                DeviceId = deviceId,
            };

            await AuthenticatorHelper.SaveAuthenticator(new AuthenticatorDTO
            {
                Name = $"(Steam){ImportAuthNewName}",
                Value = auth,
                Created = DateTimeOffset.Now,
            });
        }

View on GitHub (pinned to c16ffa08e0)

Solutions

1. Re-export the Steam Guard data with the serial_number field populated.
2. Copy the serial from the Steam mobile authenticator/account and add it to the JSON before import.
3. Validate required fields up front and report all missing ones in one message.
4. Reject the file in the UI with the specific missing field named.

Example fix

// before
if (string.IsNullOrEmpty(steamGuardModel.SerialNumber))
    throw new ApplicationException("no serial_number");

// after
if (string.IsNullOrEmpty(steamGuardModel.SerialNumber))
    throw new ArgumentException(Strings.Import_SteamMissingSerial);

if (string.IsNullOrWhiteSpace(model.SerialNumber))
    errors.Add("Steam Guard import missing 'serial_number'.");
// Combine with the shared_secret check so all missing fields are reported at once.

bool HasSerial(SteamGuardModel? m) => !string.IsNullOrWhiteSpace(m?.SerialNumber);

try { ImportSteamGuard(json); }
catch (ApplicationException ex) when (ex.Message == "no serial_number")
{
    importErrors.Add("Steam Guard file lacks 'serial_number'.");
}

When it happens

Trigger: Importing a Steam Guard JSON blob where the 'serial_number' field is missing or empty, even though shared_secret was present.

Common situations: Export omitted the serial; JSON redacted/truncated; field renamed in a newer schema; partial manual edit of the export file.

Related errors

• no shared_secret
• Import only supports otpauth://
• Import only supports otpauth://totp/ or otpauth://hotp/
• Authenticator does not contain secret
• HOTP authenticator should have a counter

AI-assisted analysis of BeyondDimension/SteamTools@c16ffa08e0 (2026-08-13). Data as JSON: /api/errors/ad5caf8eaa723049. Report an issue: GitHub.