Re-Register the file:
You can Re-register this file it by typing "regsvr32 comdlg32.ocx" from the command line in the system32 directory.
Perform the following steps to make the changes:
1. Click Start
2. In the Search bar type CMD
3. In the programs pane right click on cmd and "run as an Administrator"
4. Put in your credentials for UAC prompt
5. In the command prompt type in "regsvr32 comdlg32.ocx" then press ENTER

Also you can try downloading http://windowsxp.mvps.org/utils/Comdlg32.zip and putting it in the same directory as the HPP21 program