求助：Inno setup 6.X编译提示Type Mismatch获取硬盘序列号出错，急！！

[m0_63153534]

procedure curpagechanged(curpage: integer);
var IDLabel, RegAdr, RegURL: TLabel;
IDEdit: TEdit;
RefDisk,DiskLabel:String;
begin
  if curpage = wpUserInfo then
    begin
    if DirExists('C:\') then
    RefDisk:= 'C:\'    else
    RefDisk:= 'D:\';
    DiskLabel:= '                ';
    GetVolumeInformation(RefDisk, DiskLabel, 15, HDSerial, 0, 0, '', 0);
    IDLabel:= TLabel.Create(WizardForm);
    IDLabel.parent:= WizardForm.USERINFONAMELABEL.parent;
    IDLabel.top:= WizardForm.USERINFONAMELABEL.top+2*(WizardForm.USERINFOORGLABEL.top - WizardForm.USERINFONAMELABEL.top);
    IDLabel.left:= WizardForm.USERINFOSERIALLABEL.left;
    IDLabel.autosize:= true;
    IDLabel.font.color:= clblack;
    IDLabel.caption:= '机器码:';
    RegAdr:= TLabel.Create(WizardForm);
    RegAdr.parent:= WizardForm.USERINFONAMELABEL.parent;
    RegAdr.top:= WizardForm.USERINFOSERIALLABEL.top+(WizardForm.USERINFOORGLABEL.top - WizardForm.USERINFONAMELABEL.top)-7;
    RegAdr.left:= WizardForm.USERINFOSERIALLABEL.left + 220;
    RegAdr.autosize:= true;
    RegAdr.caption:= '注册请联系:XXXXXXXXX';
    IDEdit:= TEdit.Create(WizardForm);
    IDEdit.parent:= WizardForm.USERINFONAMEEDIT.parent;
    IDEdit.top:= WizardForm.USERINFONAMEEDIT.top+2*(WizardForm.USERINFOORGEDIT.top - WizardForm.USERINFONAMEEDIT.top);
    IDEdit.left:= WizardForm.USERINFOSERIALEDIT.left;
    IDEdit.width:= WizardForm.USERINFOSERIALEDIT.width;
    IDEdit.readonly:= true;
    IDEdit.color:= clGray;
    IDEdit.text:= GenMachineID(HDSerial);
    end;
end;