Short story (1970s or earlier) involving a lone explorer, a deserted planet, and a ship trapped in indestructible substance

I am trying to identify a short story that I read when I was a boy, so in the late 1970s/early 1980s. I read it in German, but I am certain it was translated from English. I read it in our public library, which almost certainly means it was published in the Ullstein 2000 series of anthologies (which the library subscribed to), but looking through titles on the ISFDB has produced nothing that sounds familiar.

In the story, an explorer in a one-person spacecraft discovers a hitherto unknown planet. Upon landing, he finds all signs of civilization, spaceports, streets, cities etc., however everything is deserted. He visits a city but (if I remember correctly) cannot enter any of the buildings because they are sealed with an unknown substance. On returning to his spaceship, the protagonist finds he can not longer enter his spaceship, since it is covered in the same indestructible, white substance. At some point in the story it is explained that the stuff is created by "removing the space between atoms", which makes it very hard and a perfect reflector (hence the white color).

The protagonist tries to gain access to the spaceship by shooting it to no avail, and then by banging against it with this gun, with the only effect that it "verbog den Reflektor seines Lasergewehrs", "bent the reflector of his laser rifle". The odd phrase might be an artifact of the translation, but it stuck with me, because as an avid reader of (the local language version of) Popular Mechanics I was not at all sure that lasers focus light via parabolic reflectors (also lasers were a thing that really existed, which made them lame by definition when compared to blasters and disintegrators in other stories).

Memory gets blurry after that. Eventually a member of the native population turns up and frees the ship (I think by touching it with some sort of staff or stick that makes the white stuff break and flake of). I think there is some version of THE SPEECH, i.e. how his people have moved on to some other plane of existence and have conserved their legacy for some worthy successor, but that is a bit guesswork (this was such a trope back in the day that I might be confusing several stories here). No idea how this ends.