How to create install for both 32 and 64 bit OS with Wise Package studio?

First, thanks for you share experience with me. 30 and more years in IT sound very serious .. as I know my knowledge with 10 years in IT. I'm sure that I will give you point for this question with A. But first here some clarification.

I'm installing now Windows 7 64 bit to get message of install of 32 bit application.

Let ask some other question.

My application is WinForm DotNet 2 C#2008 application which is standard database application with SQL Server 2005. It work via Internet with SQL Server and I hope our business plan to complete and we to have 100+ concurrent user with this project.
So my question is - do I have any difference in I compile my application like 64 bit ? I think that I will not have any difference in speed or any think which to worth 64 bit application, do I'm right ? My application work very fine with 2 Gb RAM & it is 100 % sure that do not need more than 4 Gb on cluent computer.
 Of course, for server with SQL Server is different, it now is 64 bit.
Of course .. it is clear that after 3 or 5 years all application will be 64 bit and 32 bit will not work at all like is now with 16 bit old application, but we have many many time until we get to this point &

Wikipedia nicely sums up Pros and Cons at http://en.wikipedia.org/wiki/64-bit . See for yourself if anything applies to your situation.

I always try to go after the problem and after the bottleneck. Doing anything else sooner or later reveals that you simply were bought at yet another marketing trick. In IT same as in all other areas of life.

If your application works ok in 32-bit version, then distribute it this way. You will have exactly half of troubleshooting cut off.

If something is not right, then find out what it is, and if it's indeed lack of 64-bit architecture, only then do 64-bit. But if it's simply wrong background color of the main form, then that's what needs to be addressed.

To vadimrapp1

Thank you for you answer .. yes , I'm agree with you and want to stay at 32 bit. But I need to be sure that my software will be installed on PC which is with 64 bit OS.

I'm installing now Windows 7 64 bit .. for 6 hours it write me that is ready at 75 % ?!? true, this is in Vurtual PC with 712 MB RAM, however seen too slow for me. Tomorrow I will tell you what error message I get when start my 32 bit install under 64 bit OS.

Usually windows 7 is installed much faster, but I recall, I saw reports about this problem. According to Datamation, "for some percentage of users it could take as long as 21 hours. "

Don't forget to run validation of your installation package, including validation for the new platforms, and using the latest Installer SDK.

While it is feasible to accomidate this, it is highly unrecommeded.  

There are differences between the Architectures that could cause multiple issues, such as Environment Variables and structure of important Registry Entries.

Whenever I have been asked to provide a "single solution" for both x86 and x64 versions, I have always created two packages.

Then, I would place each package in an identifying folder (ie. "x86" and "x64"). From there, I have a WiseScript that would simply detect the OS Architecture and based on the results call the appropitate MSI.

The end result still appears to be a single solution that can be deployed to both OSes.

To vadimrapp1

I was not able to install WIndows 7 64 bit under MS Virtual PC ... it is not possible as Virtual PC is only 32 bit.

I make test on real Windows 2008 server, I remove current package and now was able to  install from 32 bit. But somethink is not OK ... I'm sure that it give me error before. I need to make test in new clean 64 bit Windows .. probably I need to install it on new mashine ...

I choose to have only 32 bit install, will find why I have problem to run it under 64 bit OS. Thank you!