@import expected selector or at-rule, but not due to missing semicolon

I have this compass error

Line 3: Invalid CSS after "@charset" UTF-8 ": The expected selector or at-rule was" @import "compass';" )

The file looks like this. It doesn't even contain my own code

@charset "UTF-8"

@import 'compass';

      

        
        
        
      

    

I know people say this error occurs when a line is @import

missing a semicolon , but my file has a semicolon.

And the same files (scss and config.rb) can be easily compiled on Linux without issue.

Does anyone know what is wrong?

The configuration that gives the error is

• Windows 8.1
• ruby 2.1.6p336 (2015-04-13 revision 50298) [i386-mingw32]
• Compass 1.0.3 (Polaris)
• Sass 3.4.16 (Selective Steve)

I have tried many combinations

(1)
-------------------
@import 'compass';    
-------------------
// only this line, no @charset line.
// Result: compilation ok, but I need charset because 
// my COMMENTS (yes only comments) have UTF8 chars.

      

        
        
        
      

    

(2)
-------------------
@charset "UTF-8";

@import 'compass';    
-------------------
// semicolon after @charset
// Result: compilation error:
// Invalid CP950 character "\xE2"
// because the @charset line is unrecognised

      

        
        
        
      

    

(3)
// Add this to config.rb
Encoding.default_external = 'utf-8'
// https://stackoverflow.com/a/23338595/2841279
// http://blog.pixelastic.com/2014/09/06/compass-utf-8-encoding-on-windows/
// Result: compilation error: expected selector or
// at-rule, was "@import 'compass';

      

        
        
        
      

    

(4)
// Add this to config.rb
encoding = "utf-8"
// https://stackoverflow.com/a/13987672/2841279
// Result: compilation error: expected selector or
// at-rule, was "@import 'compass';