Edit: "Not Qualified" is not the right wording. Because Qualification only plays a secondary role. It is all about the licence.

In Germany carrying a gun without the right licence would be illegal possesion of a firearm.

But wait, even if you have a licence you can get fined for illegal transport and handling of a firearm.

Carrying a conceiled small sidearm without a special permit is big trouble. Transporting a firearm without a locked enclosure and not seperated from the ammunition is also a serious offence. At home you need a locked container. All in all it got so complicated that my Dad stopped storing guns at home. He sold one and put the other into the gun club. The club is really helpful, we can lend legal transport containers and for guns which we are not allowed to move in public they offer transport services for a small fee, usually that means a police officer moves the gun in his free time using legal transport containers in exchange for a beer.

Classic case: Someone dies and you find a loaded pistol in his inheritance. You bring it to the police. You did three offences: Carrying a conceiled firearm in public, carrying a firearm without proper container, carrying a loaded firearm. The legal way would have been: Calling the police to retrieve the firearm. To be honest, the state attourney usually closes those cases rather quick as "minor incident without criminal intent" but you still get a serious talk.

There are some exceptions for old historic muzzleloaders which are often fired at historic events without bullets. We don't have those so I don't know barely anything about those rules.