Usuwanie użytkownika bazy MS-SQL w InstallScript

Funkcja usuwa użytkownika bazy MS-SQL, zwraca true/false w przypadku powodzenia/porażki.

function BOOL DB_DropUser(sUserToDrop, sServerName, sDBName, sDriver, bTrustedConn, 
sUserName, sUserPwd, bLog)
OBJECT objConn, objRST;   
STRING sConnString;  
STRING  szADOConnObjID, sSQL;
BOOL bResult;
begin
    bResult = FALSE;
    if (sDriver == "") then
     sConnString = "Provider=sqloledb;";
    else
     sConnString = "Driver={" + sDriver + "};";
    endif;

 if (bTrustedConn) then
     sConnString = sConnString + "server=" + sServerName + ";";
     sConnString = sConnString + "database=" + sDBName + ";";
     sConnString = sConnString + "Trusted_connection=Yes";
 else
     sConnString = sConnString + "server=" + sServerName + ";";
  sConnString = sConnString + "uid=" + sUserName + ";";   
  sConnString = sConnString + "pwd=" + sUserPwd + ";";
  sConnString = sConnString + "database=" + sDBName;                                        
 endif;   
 
 try
  szADOConnObjID = "ADODB.Connection";
     set objConn = CreateObject(szADOConnObjID);         
    
  if (IsObject(objConn)) then 
   objConn.ConnectionString = sConnString;
   objConn.Open;                            
      
   sSQL = "IF EXISTS (SELECT * FROM sysusers WHERE name='"+sUserToDrop+"') 

BEGIN EXEC dbo.sp_revokedbaccess N'"+sUserToDrop+"' END;";   
   try
    set objRST = objConn.Execute(sSQL);
    bResult = TRUE; //Wykonano
   catch                      
     bResult = FALSE; //Błąd wykonania
     if (bLog) then WriteLog(1," - błąd usuwania loginu \""+sUserToDrop+"\" 

z bazy \""+sDBName+"\""); endif;
   endcatch;
         
         objConn.Close;         
         
  endif;
    
  set objConn = NOTHING;
  set objRST  = NOTHING;
  
 catch  
  if (bLog) then WriteLog(1," - Nie można uzyskać połączenia z bazą 

na użytkownika \""+sUserName+"\""); endif;  
 endcatch;     
 
    return bResult; 
end;