パソコンが故障したので、ハードディスクを入れ替えたので、再度ソフトを入れなおしたいがどうすればよいでしょうか？

Download and Installation Help -

https://helpx.adobe.com/download-install.html

http://www.adobe.com/downloads/other-downloads.html

If this involves software that is activated with a serial number then before youinstall again you should deactivate the old installation(s).  If you cannot do that by opening one of the programs and choosing Help -> Deactivate, then you need to contact Adobe Support thru chat and ask them to reset your activations.

For the link below click the Still Need Help? option in the blue area at the bottom and choose the chat option...

Make sure you are logged in to the Adobe site, have cookies enabled, clear your cookie cache.  If it fails to connect try using a different browser.

Serial number and activation chat support (non-CC)

https://helpx.adobe.com/contact.html?step=PHSP-PHXS_downloading-installing-setting-up_licensing-activation_stillNeedHelp