Unable to crack Excel 2007 password - what am I doing wrong?

[placencjusz]

Hello

I have been wondering about why it seems to be impossible to crack a super easy password from an Excel 2007 document.
I have created two empty xlsx documents, one encrypted with one letter password: "C" and another one with one letter password "Ć" - this is a polish letter.

C in UTF8 is 0043
Ć in UTF8 is c486

I tried to crack the C password and of course succeded with this command to launch hashcat:

• hashcat64.exe -a 3 -w 3 -m 9400 testhash-C.lst --hex-charset -1 0043 ?1
  

So i thought that it should work exactly the same way for the Ć password:

• hashcat64.exe -a 3 -w 3 -m 9400 testhash-Ć.lst --hex-charset -1 c486 ?1
  

Of course the "Ć" password is exhausted and nothing seems to make it work.
I tried to break the hex values to base code and character code by using two separate charsets - still EXHAUSTED:

• hashcat64.exe -a 3 -w 3 -m 9400 testhash-Ć.lst --hex-charset -1 c4 -2 86 ?1?2
  

Could you please tell me what am I doing wrong in this case?
I am attaching this empty file from Excel with Ć password - in case if it helps.

Thank you in advance!