WMP Error - Contact Content Provider

Introduction

I bet you see this quite often: Error code: 0xFFF00XXX blah, blah, blah if it does not help please contact your system administrator or, in case of Windows Media Player (WMP), your content provider. But what if you are that system administrator or content provider people should contact. What do you do then? You "Google" the error code and few things come up. You dismiss those search results that say to contact you and … nothing is left. It happened to me when I worked on DRM license acquisition for WMP. In this article, I would like to share my research about specific DRM error codes.

Background

Recently, as I already mentioned, I have been working with Microsoft DRM. My task was to deliver a license to a user’s desktop from a license server. Only one license was allowed per media file. If a user is not eligible to receive anymore licenses the license server would send an HTTP response with 403 status code and nicely crafted error massage in its context. Please note that DRM license acquisition utilizes HTTP.

I thought I could just simply display the error message that came with the HTTP response to the user. It would provide a pleasant experience to the user by explaining nicely and clearly about the encountered problem. It will also make me happy, as I'll able to make a simple and elegant solution. "Not so fast cowboy" – stated the WMP API – "I will give you only an error code, no access to HTTP header or/and context whatsoever, gee, and now try to figure out what those error codes mean". I can still hear its giggling.

WMP errors

I decided to conduct a simple experiment. On every license request from a user’s desktop I would send a response from an HTTP server with different HTTP status code and see what error code WMP returns.

Here is the C code that I used to request DRM licenses:

#define CLEANLICOBJ     pLicense->Release(); \
                        CoUninitialize()
                        
HRESULT GetLicenses() 
{
    CoInitialize(NULL);

    IRMGetLicense* pLicense = NULL;
    HRESULT hr = CoCreateInstance( 
                   __uuidof(RMGetLicense), 
                   NULL, CLSCTX_INPROC_SERVER, 
                   __uuidof(IRMGetLicense), 
                   (void**)&pLicense);

    if(FAILED(hr)) 
    {
        return hr;
    }

    CComBSTR bstrXMLDoc, bstrDRMVersion, bstrURL;

    hr = pLicense->raw_GetDRMVersion(&bstrDRMVersion);
    if(FAILED(hr)) 
    {
        CLEANLICOBJ;
        return hr;
    }

    hr = pLicense->raw_GetSystemInfo(&bstrXMLDoc); 
    if(FAILED(hr)) 
    {
        CLEANLICOBJ;
        return hr;
    }

    char url[1024];
    for( int i = 0; i < STATUSCODESMAX; i++ )
    {
        sprintf(url, 
          "http://localhost/HttpErrorProducer/default.aspx?statuscode=%d", 
          httpStatusCode[i].StatusCode);
        bstrURL.Append(url);
        hr = pLicense->raw_GetLicenseFromURL(bstrXMLDoc, bstrURL);
        printf("\n0x%X\t\t%d\t%s", hr, 
                              httpStatusCode[i].StatusCode, 
                              httpStatusCode[i].ReasonPhrase);
        bstrURL.Empty();
    }
    CLEANLICOBJ;
    return S_OK;
}

Here is an excerpt of ASP.NET server side code:

protected void Page_Load(object sender, EventArgs e)
{
    int code = Convert.ToInt32(Request["statuscode"]);
    HttpStatusCode statusCode = 
                       HttpStatusCode.GetStatus(code);
    Response.StatusCode = statusCode.StatusCode;
    Response.Write(statusCode.ReasonPhrase);
}

Now this is the time for the error codes:

Error Code	HTTP Status Code	HTTP Reason Phrase
0xC00D2712	200	OK
0xC00D275E	201	Created
0xC00D275E	202	Accepted
0xC00D275E	203	Non-Authoritative Information
0xC00D275E	204	No Content
0xC00D275E	205	Reset Content
0xC00D275E	206	Partial Content
0xC00D275E	300	Multiple Choices
0x80072F76	301	Moved Permanently
0x80072F76	302	Moved Temporarily
0xC00D275E	303	See Other
0xC00D275E	304	Not Modified
0xC00D275E	305	Use Proxy
0xC00D275E	400	Bad Request
0xC00D2EFB	401	Unauthorized
0xC00D275E	402	Payment Required
0xC00D2EFB	403	Forbidden
0xC00D2EE6	404	Not Found
0xC00D2EE3	405	Method Not Allowed
0xC00D275E	406	Not Acceptable
0xC00D2EF6	407	Proxy Authentication Required
0xC00D2EE6	408	Request Time-out
0xC00D275E	409	Conflict
0xC00D275E	410	Gone
0xC00D275E	411	Length Required
0xC00D275E	412	Precondition Failed
0xC00D275E	413	Request Entity Too Large
0xC00D275E	414	Request-URI Too Large
0xC00D275E	415	Unsupported Media Type
0xC00D2EE2	500	Internal Server Error
0xC00D275E	501	Not Implemented
0xC00D2EE4	502	Bad Gateway
0xC00D2EE6	503	Service Unavailable
0xC00D2EE5	504	Gateway Time-out
0xC00D275E	505	HTTP Version not supported

HTTP Status code 100 – "Continue" and 101 - "Switching Protocols" are not included as they would hang HTTP communication as they are suppose to.

The following error codes are worth noticing:

• 0xC00D2712: WMP has not received a license blob.
• 0xC00D2EFB: WMP likely has no credentials required to access to the server.
• 0xC00D2EE6: more likely to occur when WMP hits a wrong URL.
• 0xC00D2EE2: it is definitely time to contact the content provider!.
• 0xC00D275E: just very popular ;~).

Conclusion

I hope this article sheds some light on WMP error codes. Also you can find a sample of C code to request a license from a DRM server.

References

Please check these useful links for Windows Media Player error codes:

• Troubleshooting Windows Media Player 10 Error Messages
• Error Codes and Messages
• Windows Media DRM Individualization Best Practices
• freesoft.org