Hello.
First… Sorry for my bad english! 
Can I write in german language here?
Second… This is my first post here. I hope this is at the right place.
Then…My problem…
I have a .skp wich i can not open.
The error is:
“Es scheint sich nicht um eine SketchUp-Modell zu handeln.”
If I want to import this file, the error is:
“Datei nicht gefunden oder ungültig.”
What can I do???
What happend?
Greetings Daniel
What does this have to do with SketchUp Free (web)?
Where did you get the SketchUp file? In which version was the SketchUp file made? Share the .skp file so we can see what you are working with.
Sorry, I have download Sketchup Make 2017 for a long time.
I think its from the sketchup website.
I never paid for it, so I think here in “Sketchup Free” is the right place.
This file (Ufoversuch.skp) I have created myself.
Hmm…???
I can not upload this file.
“Processing Upload” since over 30minutes.
Greeting Schreddl
No. This category is for the free web version of SketchUp. I’ll move it to the correct caetgory.
Very likely it’s over the 16 Mb limit. Upload it to ropBox of WE Transfer and share the link.
Processing: Ufoversuch.skp…
Ok, thank you for moving in the correct category.
The file has just 1232kb.
And I can not copy it in another folder!?!?
Something’s clearly wrong with the file or your computer.
Did you try uploading the file to DropBox?
Can you find the .skb file and share that?
If the file is that small, there must not be a whole lot in it. Maybe it would be easiest to start over.
Hmmm, now, when I want to copy the file, there is an error.
Google says, I had to check the USB drive.
Windows want to repair it.
I will try this.
Perhaps I can open the file then.
An Upload to Dropbox or other sites I haven’t tried yet.
First I will try to repair the USB Stick.
No…the project in this file is not big. Something for 3D Printing.
But I needed houres and days to build it.
Greetings Schreddl
So you’ve been saving the file to a USB drive? That’s probably the issue. You should never work on files saved directly to USB drives or other locations that are not internal to the computer.
Maybe you can do it more quickly the second time.
I’m working at two diffrent PC’s.
At every PC is the same version of Sketchup Make 2017 installed.
Saving in a cloud is no option.
So I have to save at USB Stick.
This is the first time that I have a problem like that.
I use Sketchup since 2010.
But…never had such a problem. 
If this “repair thing” won’t work, I had to build this “Thing” once again.
And Yes…I hope I get it quicker this time.
Save the file to the internal drive. Copy it to the USB stick when you need to take it to your other computer. Copy it from the USB stick to that computer’s drive before opennig it and working on it.
Ok.
This will work!
I will do it so the next time.
So… repareing is done.
I can copy it.
But I still can’t open the file in Sketchup.
Ufoversuch.skp (344 KB)
Looks like it’s been corrupted by the issues you had with the USB memory stick. At this point I would suggest you move on and redo the model correctly making sure you are saving it to the internal drive on your computer.
That means:
No chance to repair this file? 
An simple lightning effect for disco or clubs or the private Partybasement.
40 LEDs controlled with DMX.
It looks like an UFO! 
USB sticks wear out much faster than traditional hard drives when used for continuous saves. Applications often keep reading and writing temp data to the drive where an open document is stored. That is why they should be used only for backing up and transporting data.
Ok…I will change my “Saving and Working” procedure!
Couldn’t do anything, the file is random data and not a SketchUp model.
Du musst deine Sketchup Dokumente auf deiner Computer internen SSD oder HDD speichern.
Es ist bekannt, dass das Speichern des Dokuments auf einem externen Gerät solche Probleme verursacht