Yes. this is a gigantic file, 86.6 GB!
When I created this file, Photoshop immediately claimed 115 GB scratch disk, so if you have only 50 GB free, that's probably the reason you can't create it.
What is this file going to be used for?
If it's for printing, you probably don't need more than 100 pixels per inch. (you have entered 300 pixels per centimeter, which equals 762 pixels per inch (PPI).
Note that there is no generic CMYK profile, you have to talk to the printer about which profile to use.
US Web Coated is just the default, and is not a profile that's used in Europe.
Also, the normal procedure is to work in RGB, and then convert to CMYK once you're done.
This will also let you work on a file that's 25% smaller (file size) than in CMYK.
