I am having the same "Unexpected file format" issue!

Continuing the discussion from The Dreaded - Unexpected file format:

The only extension I’ve downloaded and used is "LightUp"
I have a lo of time into this model and really need some help recovering
the file is 10MB. how can i send this for your review.
i appriciate any help as i will be screwed otherwise

Upload the file to DropBox and share the link.

I can’t open it. I get a message indicating it isn’t a SketchUp file. Maybe someone from the Sketchup team will be able to do something with it.

thanks for attempting DaveR.
i had finished putting my lighting to the model on friday. I then saved it to a thumb drive to be certain i had a back up. i got to the office this morning and after turning my Mac Book on i noticed the model file wasn’t in my Documents. i grabbed my thumb drive while patting myself on the back for making a back-up and then… “not a sketch up model”… dammit!

Do you have a backup file? On OSX there should be a ~ before the file name I think.

well there is one from the 5th. nothing from the 6th. all of which i spent working on this model.