TU Berlin 2FA: how to set up an authenticator app for your TUB account

At Technische Universität Berlin (TU Berlin), students and staff sign in to the TU Portal and other IT services with their TUB account. A second factor isn't optional: most services run by the ZECM, the university's IT center, need one, and you can only swap one method for another (TU Berlin).

TU Berlin calls each one-time code a TAN. You get them from an authenticator app (the TOTP procedure, which the ZECM recommends) or a numbered TAN list. Text-message codes (mTAN) still work for existing users but can't be set up anymore. Any TOTP app is allowed (TU Berlin). This guide uses Authenticator App - Novaz on iPhone; other apps work the same way.

How we checked this guide: the TU Berlin steps come from the ZECM's own help pages, in English and German and including their screenshots, linked below, which we read on October 21, 2026. We haven't tested them on a TUB account, so a label may differ slightly. The Novaz steps are checked against the app, version 1.0.5.

Before you start: keep the app off your sign-in device

The setup screen advises against putting the authenticator on the device you use to sign in to TU services, and asks you to give the app camera access only (TU Berlin). So open the TU Portal on a computer and scan from your iPhone. You can choose the app when you activate your account or switch to it later (TU Berlin).

Turn on the TOTP procedure in the TU Portal

The ZECM's how-to, last updated December 22, 2022, lists these steps (TU Berlin). Its screenshots show the portal in German, so the German label follows in brackets.

1. Go to www.tu.berlin and choose Login (Anmelden) to open the TU Portal.
2. Sign in with your TUB account name and password.
3. Enter a code from your current method, an app or your TAN list, and choose Continue (Weiter).
4. Under My data (Meine Daten), choose the My profile (Mein Profil) tile, then TAN management (TAN-Verwaltung).
5. On the TOTP token procedure (TOTP-Token Verfahren) card, choose Setup (Einrichten).
6. Choose Create new TOTP (Neues TOTP erstellen). A QR code appears.
7. In Novaz, tap +, then Scan QR code, and point the camera at the screen. A new entry called "TU Berlin" shows a 6-digit code that changes every 30 seconds.
8. Type that code into the Token field and choose Submit (Absenden).

A green check mark on the TOTP card shows it's now your active method. TU Berlin's how-to shows only a QR code, with no key to type. If the portal is open on your iPhone anyway, take a screenshot and use Choose a photo in Novaz (how that works), then delete it from Photos or store it as safely as a TAN list.

TU Berlin has no backup codes: keep the QR code

TU Berlin's help describes no backup codes for the app method. It does say the QR code should be guarded like a TAN list, and that if you still have it, you can set up another device with it (TU Berlin). If you keep it, a printout in a locked drawer beats a photo on the same phone. The pages treat the TAN list as a method you switch to, and don't say whether an old list still works while the app is active.

Unless you've backed up Novaz with iCloud backup or a backup file, its keys exist only on your iPhone, and TU Berlin asks you to keep the app for your whole time at the university (TU Berlin).

When TU Berlin asks for a code

You'll type a code after your password whenever you open one of TU Berlin's specially protected services, and some services use a code to confirm actions (TU Berlin, TU Berlin). The pages don't list which services those are.

If TU Berlin rejects your code

The ZECM's FAQ gives two causes: each code is valid for only 30 seconds, and the phone's clock must be very accurate (TU Berlin). On iPhone, open Settings > General > Date & Time and turn on Set Automatically. Novaz also warns you when the clock is 15 seconds or more off. More causes are in Authenticator code not working?

Moving to a new iPhone

While you can still sign in, open TAN management, choose Regenerate (Neu generieren) on the TOTP card, which TU Berlin names for a new smartphone, and scan the new QR code on the new phone (TU Berlin). A kept original QR code works too. So does a Novaz iCloud backup or backup file, which restores your accounts on the new iPhone with the same codes. See How to transfer your authenticator app to a new iPhone.

If you lose your phone

If you kept your QR code, scan it on your new device. If not, the only documented route is in person: bring a passport or national ID card to the ZECM IT Service Desk, and after checking it, staff give you a new QR code. Install your app before you go (TU Berlin, TU Berlin).

The desk is in room E-N 024, Einsteinufer 17, open Monday to Friday, 10 am to 1 pm. The hotline, +49 30 314 28000, answers weekdays from 2 pm to 4 pm, but the pages don't say it can reset a lost authenticator. See also Lost the phone with your authenticator app?

Can you turn it off?

No. You can only switch to a TAN list under TAN management (TU Berlin). Text-message users can leave mTAN, but only by moving to the app or a TAN list, and their phone number can no longer be changed.

Official TU Berlin help

• Two-factor authentication
• TOTP procedure
• Two-factor authentication – TAN management TOTP token
• Zwei-Faktor-Authentifizierung - TAN-Verwaltung TOTP-Token (German, with screenshots)
• Two-factor authentication – TAN management TAN list
• TUB-Account (German)
• Zwei-Faktor-Verwaltung (German)
• IT Service Desk