There are two possibilities for visa applicants from Cambodia:
1. The applicant contacts the French Embassy in Phnom Penh, with which Norway has a representation agreement, to submit an application there. The applicant must then check the website of the French Embassy on how to proceed and what documents are required. The application will be processed by French officers, and applicants will be interviewed at the French Embassy. The Norwegian Embassy in Bangkok has nothing to do with this process and cannot intervene in the French proceedings. This also applies if the visa application would be rejected by the French Embassy in Phnom Penh. It is not possible to register on the UDI's Application Portal because the application is not being processed by the Norwegian authorities, but by the French authorities under a representation agreement between Norway and France.
2. The applicant travels to Bangkok and deliver the application to the Norwegian Visa Application Center in Thailand. Citizens of Cambodia can then choose to wait in Thailand for a response, or get his/her passport in return and go back to Cambodia. The applicant must then come back to Bangkok when result is available. Please visit the webpage of the Norwegian Embassy in Bangkok to see how you can apply.
Citizens from Cambodia who wish to apply for a residence permit in Norway has to come to Bangkok (alternative 2 above).