Error 1720 when installing CS3 on Win 7 64-bit home premium

Question

I've been directed to the Forum for help as the Support Tech said she could not help me as they only help with CS5.  She said that CS3 WON"T WORK on a Windows 7 machine and yet I have googled and found people who have had it work.  She then told me that they will probably experience lag and other errors once they start using it more fully.  I smelt BS right about then in that conversation.  She couldn't confirm that if I purchased CS5 upgrade that my CS3 upgrade would qualify as upgrade.  Yeah, I'm really going to spend $800 to find out (not).
Basically it ended where I either buy CS5 or go the Adobe Forums for help.
So okay here I am.  Long post (sorry) but want to get all the fact out there.
I purchased CS3 back in 2008 and installed on my XP machine.
Just purchased a new laptop with Windows 7 64-bit home premium.
Tried to install CS3 and as soon as it tries to install I get this message:
Setup has encountered an error and cannot continue.  Contact Adobe Customer Support for assistance.
Error 1720.  There is a problem with this Windows Installer package.  A script required for this install to complete could not be run.  Contact your support personnel or package vendor.
I have tried the following solutions (found on Google), none of them work:
1) installing in safe mode (with just Windows features in the start up)
2) redownloading the files to ensure I didn't have a corrupted version
3) installing as Administrator
4) deregister/register Windows Installer
5) looked for update to Windows Installer but mine is up to date
6) checked that Windows Installer had "started" on my laptop (yes)
7) used Adobe cleanup utility
8) used Adobe licence recovery (Acrobat Pro (CS3) wouldn't get past the licence stage although it did install)
Support Tech lady said that no old CS software would work on Windows 7 BUT last night I installed Photoshop CS Version 8 and it installed perfectly.  What I noticed different is that PS CS V8 used Installshield whereas CS3 I am told didn't use Installshield.
So I am left with my new laptop using PS CS V8 with Dreamweaver MX.
BTW Dreamweaver MX installed okay and it used Installshield too - so is that the reason CS3 won't install - it not using Installshield?
Does anyone have any solutions not tried above?
Am I just going to have to use old software on my Win7 machine?
Thanks in advance.
Sarah

Answer 1

Hi Bob,
Thank you for your reply.
Yes I have tried the CS5 Cleanup Tool - multiple times.  Doesn't help.
I am surprised to hear that you installed with no problems in light of Tech Support being adament that it won't work on Windows 7 and is not supported.
I told Tech that I didn't accept that as there are probably hundreds of thousands of users with CS3 who have installed or tried to install on a Win7 machine and not everyone has hundreds of dollars spare to upgrade.
I only really use DW, PS and Acrobat in the Suite so I'm going to have to save to buy those products but it won't be anytime soon.
Thanks.
Sarah