After many attempts I've not been able to create a new project, this is the answer:
"Sorry, we couldn't download your project files
- Problems with internet connection
- Maintenance works at Salesforce"
But this is not correct.
- File - New - Project - OK - Use OAuth for authentication. Result: Error
- File - New - Project - OK - Salesforce environment: Sandbox - UserName - Password - Security Token. Result: Error
I've couldn't determinate the reason on my own. Please help!