i-Kfz error messages: the most common online registration errors and what actually helps
Zuletzt aktualisiert: 3. September 2026
The most common error messages in the i-Kfz portal, what is behind them and what actually helps: an overview from daily practice with registration offices across Germany.
In short
Online vehicle registration via i-Kfz rarely fails because of the procedure itself; it almost always fails on one of a few known problems: unreadable or mixed-up security codes, vehicle documents issued before 2015 without codes, an error message about a different responsible office after a move, a missing SEPA mandate for the vehicle tax, or a session that expired in the middle of the application. The good news: each of these problems has a clear way out, and if you lay out all documents before you start, you will usually get through without visiting the office. This overview explains the most common error messages in the i-Kfz portal, what is behind them and what actually helps. It is based on our daily work with registration offices across Germany. Unless noted otherwise, everything applies equally to deregistration, re-registration and new registration. At the end you find answers to the three most common basic questions about ID, portal outages and service providers.
Why does the i-Kfz portal abort in the middle of the application?
The portal ends the session after a short period of inactivity, and all entered data is gone. This typically happens when you only start scratching codes free or searching for documents during the application. The solution is unspectacular but saves the most common frustration: lay everything out before you start. For a deregistration that means registration certificate part 1, both license plates and the uncovered security codes. For re-registration and registration you also need part 2, the proof of the roadworthiness test, the eVB number from your insurer and the bank details for the vehicle tax.
Online car deregistration: process and documents at a glance
What if the security code is not accepted?
The hidden codes on the certificate and the plate seals are the most common stumbling block. Three typical causes: First, characters get mixed up, such as capital I, lowercase l and the digit 1, or capital O and zero. When in doubt, compare the character height with the neighboring characters. Second, scratching too hard damages the code itself. Third, a code is entered in the wrong field, for example the code of the front seal in the field of the rear one. If a code is genuinely unreadable, there is no way around the office, because the document or seal must be replaced.
Why does the portal say online registration is not possible?
Behind this generic message there are usually concrete reasons. The most common: the vehicle documents were issued before 2015 and carry no security codes at all. In that case the digital route is not possible with these papers. Other typical causes are holder data that no longer matches after a move or marriage, outstanding vehicle tax, and special cases such as classic-car or seasonal plates, which not every office offers digitally.
What does the message about a different responsibility mean?
If you moved and kept your plates, you often end up at the wrong office: the responsible office is always the one at the holder's current place of residence, not the one whose code is on the plate. The registration certificate gives the right hint; it names the issuing office. On the portal of your current local office the application then usually goes through immediately.
Why does the portal require a SEPA mandate?
For registration and re-registration the SEPA direct debit mandate for the vehicle tax is mandatory; without bank details you cannot continue. If you want to avoid the direct debit as such, there is no alternative in the online procedure; that is how the law prescribes it.
The application was approved, but plates and certificate have not arrived. Is that normal?
Yes. The approval arrives digitally and immediately; the office sends the new documents and seals by post, and how long that takes varies by office. Until then the provisional registration proof from the portal applies; its validity period is stated on the document itself. If you want to know how busy your registration office currently is, our waiting-times index has daily data.
Do I need an electronic ID card for i-Kfz?
For private use of the official portal, yes: you need the ID card with the online function activated, the matching PIN and the AusweisApp with a suitable smartphone or card reader. If you no longer know the PIN, you can have it reset at the Bürgeramt. Alternatively a registration service files the application through its own official access, which removes the ID hurdle.
My city's portal is down. What now?
The portals of individual regions have regular maintenance windows, often on weekends. It usually helps to file the application a few hours later or on the next working day. For longer outages, the remaining routes are a service provider with its own access or the office itself.
Is a registration service worth it when the portal fails?
It depends on the case. If you meet the technical requirements and your vehicle papers carry codes, you will often get through the official portal yourself. A service provider makes sense when the eID route is not possible, the portal rejects the case, or you simply lack time and patience. You can recognize serious providers by the fact that they state final prices including all fees and file the application through the official interfaces.
Portal failing or requirements missing?
We handle your registration or deregistration Germany-wide with a power of attorney, without AusweisApp and without a trip to the office. Enter your details online, sign the power of attorney digitally, and we file the case through the official interfaces.