The most striking example is undoubtedly that of Neder-Over-Heembeek, where it quickly came to light that census taking had been carried out "haphazardly". Officers sent over from the Brussels Civil Registry Office in June 1921 noted that the population registers had not been properly kept and, as a result, they did not accurately reflect changes that had occurred within the municipality (lack of information regarding the locations and dates of inhabitants' residential addresses, the civil status of households and marriage ceremonies; numerous unregistered deaths and births; lack of internal references between the index and the registers, making the task of finding a person or an address impossible, etc.).

On the 12th August 1921, the Board of Mayor and Aldermen met in Brussels and issued a ruling that disciplinary measures would be taken against the former Municipal Secretary of Neder-Over-Heembeek. The Director of the administrative district subsequently decided to carry out a thorough verification of the former municipality's registers and supplement them with any information that was now able to be collected from its inhabitants.

The overhaul of these registers, which began on the 24th August, was soon completed on the 28th October of the same year thanks to the “extraordinary effort” put in by the Brussels officer tasked with carrying out this assignment. The officer in question took a multi-pronged approach to getting in touch with the general population, walking up and down streets throughout the district to meet residents out working in the fields or out of the home. In doing so, he realised that many people had never been accounted for, while some registrations, drawn up without the consent of the citizens concerned, bore false signatures. As a result of those 64 days of intense work (to which the officer devoted his Sundays), 1132 household registrations were drawn up, 417 new registrations were submitted, 704 old registrations were corrected and 18 registrations were withdrawn.

In March 1922, a letter from the Director of the Registry Office also reported the disappearance of street signs located within the boundaries of the former municipality of Neder-Over-Heembeek, as well as the almost total absence of numbers on the front of houses. According to the information gathered by the Head of the 9^th District, these nameplates are believed to have been removed before annexation and given to a painter for restoration, but this work was never completed.

Maybe the numerous street name changes planned for December 1922 made this restoration work unnecessary? Nevertheless, the Director of the Civil Registry Office, anxious to put an end to the "litany of errors" - which were in no way helped by the chaos reigning in the population register - ordered the Chief Engineer of Public Works to have the street signs repainted and put back in the appropriate places, while affixing house numbers to the front of any houses not displaying them.