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Extract Window Product Key - With an API !

, 21 Aug 2006
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Get a window's product key!


Hi. This article shows a very usuful function!! This function gets a window's product key using the Windows API that can used with any window and can be used with any tool and language, VB, C++, VS6, VS 7, 8, and so on.

The code

BSTR GetProductKey()
 Window Product Key Extract

 CString strResult;        //Return a Window Product Key
 HKEY hRegistryKey;        //Registry Handler 
 BYTE   *DigitalProductID; //Digital Product Key Value 
 DWORD DataLength;         //Digital Product Key Length 

 BYTE ProductKeyExtract [15]; //Extract Key 

char sCDKey  [256];   //Temp, adding a Window Product Key
 long ByteCounter;    //Counter
 long ByteConvert;    //Convert

 int  nCur;      //XOR calculate 

 char *KeyChars[] = {

 // HKLM\\SOFTWARE\\MICROSOFT\\Windows NT\\CurrentVersion 열기  
    &hRegistryKey) == ERROR_SUCCESS)
  DataLength = 164; 

  //Allocate Memory
  DigitalProductID = (BYTE *)malloc(DataLength);    

  //Memory Initializationd
  memset(DigitalProductID, 0, DataLength); 

 //Digital Product Key Open

  if(RegQueryValueEx(hRegistryKey, "DigitalProductId", 
   NULL, NULL, DigitalProductID, &DataLength) == ERROR_SUCCESS)
   //reading a value start position 52, by 66
   for(ByteCounter=52; ByteCounter<=66; ByteCounter++)
    ProductKeyExtract[ByteCounter - 52] = 

   //Last Indexer
   ProductKeyExtract[sizeof(ProductKeyExtract)] = NULL;

 //Start Converting job, Next Step 

 memset(sCDKey, 0, sizeof(sCDKey)); 

 for(ByteCounter=24; ByteCounter>=0; ByteCounter--)
  nCur = 0; 

  for(ByteConvert=14; ByteConvert>=0; ByteConvert--)

   nCur = (nCur * 256) ^ ProductKeyExtract[ByteConvert];  //XOR&#44228;&#49328; 
   ProductKeyExtract[ByteConvert] = nCur / 24;
   nCur = nCur % 24;
  strcat(sCDKey, KeyChars[nCur]);

  //Insert "-" 

  if(!(ByteCounter % 5) && (ByteCounter))
   strcat(sCDKey, "-"); 

 //Insert Product Key into Return value 

 strResult.Format("%s", sCDKey); 

 //Close Registry

 //Release Memory
 if(DigitalProductID) free(DigitalProductID); 

 return strResult.AllocSysString();

If you have any questions, mail them to me!


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About the Author

United States United States
Yeah, I'm programmer in SEOUL, Korea.

Comments and Discussions

QuestionCouple serious bugs in this Pinmemberpickaname26-Nov-13 12:20 
AnswerRe: Couple serious bugs in this Pinmemberhandsomeme8-Apr-14 3:01 
GeneralWork version is here [modified] Pinmemberdima_kdl30-Jan-09 8:03 
GeneralRe: Work version is here Pinmembertttony0725-Aug-09 18:36 
AnswerRe: Work version is here Pinmemberdanielsage6-Feb-11 12:07 
GeneralRe: Work version is here Pinmembertttony076-Feb-11 15:46 
GeneralC# & VB.NET Code Pinmembercrouchie19984-Apr-07 6:46 
GeneralNice code PinmemberDouglas R. Keesler6-Jan-07 21:15 
GeneralSmall bug Pinmembermcanti6-Jan-07 4:42 
GeneralRe: Small bug Pinmembersstraw17-Oct-07 13:21 

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