Kontaktadressen står i registreringen.

Because kontaktadressen is in the definite form: the contact address.

In Norwegian, definiteness is usually added as an ending:

• en kontaktadresse = a contact address
• kontaktadressen = the contact address

So the sentence is talking about a specific contact address, not just any contact address.

In Norwegian, the is usually attached to the noun as a suffix instead of being a separate word.

Compare:

• en adresse = an address
• adressen = the address

So:

• kontaktadressen = the contact address
• registreringen = the registration

This is very normal in Norwegian.

Yes, står literally means stands, but in Norwegian it is also often used in the sense of:

• is written
• is listed
• appears
• is stated

So in this sentence, står does not mean that the address is physically standing somewhere. It means the address is recorded or shown in the registration.

This is a very common Norwegian usage. For example:

• Det står i boka. = It says so in the book.
• Navnet står på listen. = The name is on the list.

Sometimes, but it would change the nuance.

• Kontaktadressen står i registreringen.
  = The contact address is listed / appears in the registration.

• Kontaktadressen er i registreringen.
  = The contact address is in the registration.

The version with står sounds more natural if you mean that the information is written there or officially recorded there. Using er is more general and less idiomatic in this context.

I usually means in.

Here, i registreringen means something like:

• in the registration
• in the record
• in the registration entry

Norwegian often uses i for information that exists inside a document, system, record, or entry.

So the sentence treats the registration as a place where information is contained.

For the same reason as kontaktadressen: it is in the definite form.

• en registrering = a registration
• registreringen = the registration

So i registreringen means in the registration or in the record.

It is one compound noun, which is very common in Norwegian.

It is made from:

• kontakt = contact
• adresse = address

Together:

• kontaktadresse = contact address
• kontaktadressen = the contact address

Norwegian often writes compounds as a single word, where English may use two words.

Other examples:

• telefonnummer = telephone number
• e-postadresse = email address

This is the normal Norwegian word order for a simple statement:

• subject: Kontaktadressen
• verb: står
• prepositional phrase: i registreringen

So it follows the basic pattern:

Subject + verb + other information

Very straightforward.

This is a good question because Norwegian gender can be flexible in Bokmål.

Adresse is often treated as a feminine noun, but in Bokmål many feminine nouns can also be used as common gender with en and -en.

So you may see:

• en adresse – adressen
• sometimes also ei adresse – adressa

In formal and general Bokmål, adressen is very common.
That is why kontaktadressen looks perfectly normal.

Yes, it is natural, especially in administrative, official, or technical contexts.

It sounds like something you might see in:

• a database system
• a form
• official correspondence
• instructions about registration details

It has a slightly formal or bureaucratic tone, which fits the vocabulary.

Yes. Depending on context, it could be rendered as:

• The contact address is listed in the registration.
• The contact address appears in the registration.
• The contact address is recorded in the registration.
• The contact address is entered in the registration record.

That is because står is broader than the literal English stands in this kind of sentence.