One thing I forgot is that you need to add "\0" your string pre-encoding (or "\0" to your post-encoding). Win32::API will add the byte \0 for you, but the char \0 is expected (which is encoded as two \0 bytes).

So what's the error message? I bet it can be fetched via GetLastError (and a quick look at the docs would confirm that).

thanks for your answer ...
I added "\0" to the string but there is no change.
I dont get any error message it just returns 0 as filehandle.
my $hWim = $wimfile->Call(... #returns 0 see code above
"sry for double post"

You haven't added

use strict;
use warnings;
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Here is my code ...

use Win32::API;
use Data::Dumper;

use Encode qw( encode );

#API FUNCTION WIMCreateFile
# HANDLE
# WINAPI
# WIMCreateFile(
#     LPWSTR  lpszWimPath,
#     DWORD   dwDesiredAccess,
#     DWORD   dwCreationDisposition,
#     DWORD   dwFlagsAndAttributes,
#     DWORD   dwCompressionType,
#     LPDWORD lpdwCreationResult
#     );



my $filehandler = encode('UCS-2le', "C:\\test.wim");


#Code example in C
#TCHAR *wimFile    = TEXT("C:\\sample_image.wim");  

my $wimfile = new Win32::API("wimgapi", "WIMCreateFile", ['P','N','N',
+'N','N','N'], 'N');
my $hWim = $wimfile->Call($filehandler,
                           WIM_GENERIC_WRITE,
                           WIM_CREATE_NEW,
                           0,
                           0,
                           0);

#Code example in C
# hWim = WIMCreateFile ( wimFile,                               //exis
+ting .wim file to append to
#                        WIM_GENERIC_READ | WIM_GENERIC_WRITE,  //acce
+ss mode
#                        WIM_OPEN_EXISTING,                     //open
+ flag
#                        0,                                     // or 
+WIM_FLAG_VERIFY flag for file corruption check
#                        0,
#                        &created );



print $hWim;
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